0

## Kayles - a game you can always win!

Published on Sunday, June 27, 2010 in , , , , ,

Picking up from the Fairy Tales post, let's talk specifically about Rip Van Winkle. Shortly before the American Revolution, he wandered up into the Catskill Mountains, where he is supposed to have run into a group of men playing a variation of nine-pins/skittles (shortly before drinking their liquor and sleeping for 20 years).

Let's take a closer look at one variation of nine-pins, introduced in 1857 in Henry Ernest Dudeney's The Canterbury Puzzles as kayles (rhymes with ”tales”).

The rules of kayles are fairly simple. A ball is rolled at a line of wooden pins. The ball is of such a size that it could knock down either a single pin, or two pins that were right next to each other. Two players take turns, and the winner is the person who knocks down the last pin.

When playing with a real ball, the challenge is a combination of strategy (which pins will give you an advantage?) and skill (can you knock down the pins you want?). For the rest of this article, we're going to assume that the game is played by two skillful players who can hit the pins they desire everytime. This way, we can examine the strategy.

Let's start with a line of 5 object (coins, for example), using an O to represent an individual coin in the set-up:

`OOOOO`
Assume the first player “knocks down” (takes away) the object 2nd from the left, leaving this set-up (a dot will represent a removed object):
`O.OOO`
The 2nd player could knock down the left-most pin, the 3rd (counting from the left) 4th, or 5th pin. The player could also knock down the 3rd and 4th pins, or the 4th and 5th pins, but not the 1st and 3rd pins (they're too far apart to knock down together). Let's say he decides to knock down the 4th & 5th pins:
`O.O..`
From here, it's not difficult to see that the 2nd player will win. The 1st player can only remove 1 of the pins, and then the 2nd player will remove the other to win.

Before we continue, try playing kayles (Java required) against your computer. If you click just to the left of the number of pins (skittles), you can decrease them down to 10. If you click just to the right, you can increase them to 60. Leave the Full circle box unchecked, so that two random pins will always be removed.

I'll wait while you try the game out for yourself...

...Yes, it's frustrating to lose to the computer so often, isn't it? Those of you who are familiar with nim might suspect that a similar strategy to be used here.

Kayles is different enough that you can't use straight nim strategy in it. However, there are ways to win, and I'm going to teach you how to win in games with up to 16 objects. As long as you play perfectly, and the other person doesn't know kayles strategy as well as you do, you can always win. If they do know kayles strategy as well as you do, you can still get the advantage by going first.

If a board had only two pins is a row, the first player could always win by just taking those 2 pins. 3 pins in a row? The first player removes the center pin, forcing the 2nd player to take just 1 of the remaining ones, leaving the other for the first player. The same could be done with 4 pins in a row, by taking the 2 center pins.

What about 5 or more in a row? All you have to do is go first, and you can give yourself a similar advantage! How?

If there are an odd number of pins in a row, simply remove the center most pin. For a row of 11, you would remove the centermost one, leaving 2 groups of 5:
`OOOOO.OOOOO`
If there an even number of pins in a row, you just remove the two pins in the center. For a row of 10, here's how the board should look after you remove the center two, leaving 2 groups of 4:
`OOOO..OOOO`
From this point on, all you have to do is mirror the moves made by your opponent, and you'll always be the last to move! Try the Kayles game again, with the settings starting at 10, and keep clicking Reset, until it gives you a single unbroken line of pins. You'll quickly see how and why this is an effective strategy. (It's fun when you start winning, isn't it?)

But what about those games when you start with a broken row? Here's where you need to memorize some “safe” groupings that you can leave the other player without fear of losing. Because the groups below only work for groups of no more than 9 cards each, the following approach really only works well for up to 16 cards.

Besides leaving two equal chains, as described above, here are the safe arrangements of 2 groups: 1–4, 1–8, 2–7, 3–6, 4–8, and 5–9. You could remember these groups with help from the Major System, but they're easily remembered by rote, as well.

Sometimes, you'll need to leave three groups instead of two. Memorize these three sets: 1, 4, and 8 (first set); 2 and 7 (second set); 3 and 6 (third set). If you can leave three groups, each containing a number from a different set (such as 4, 2 and 6 – or even 1, 2, and 3!), then you've left yourself in a safe position.

Let's try this out with a puzzle of 10 pins as generated by the kayles page we've been using. It just gave me this arrangement (placed here in a straight line, instead of a circle, and with a dot representing the pre-removed pin):
`OOO.OOOOOOO`
That's a group of 3, and a group of 7. What are the options here? Well, it could easily be reduced to the safe groups of 3 and 6, so let's do that:
`OOO..OOOOOO`
The computer played so as to leave the following arrangement:
`OOO..OO.OOO`
Here's where I have to start thinking about groups of three. Remember the sets (1,4,8 – 2,7 – 3,6)? A quick look here reveals that it wouldn't be tough to leave a group of 1, 2, and 3 (by removing two pin from either of the groups of 3, which would be one number from each of our three memorized sets! Let's do that:
`OOO..OO...O`
The computer decided to remove the solo pin:
`OOO..OO....`
At this point, all I have to do is fall back on the original strategy of leaving two equal groups and mirror the computer, and I'll win! I remove one pin from the group of 3:
`.OO..OO....`
No matter where you go from here, it's not hard to see that the computer can't win.

Memorize these strategies, and practice applying them by playing against the computer (start with 10, and work your way up to 16).

When challenging someone, ask them to set out 16 objects in 1 or two groups, and explain the rules to them. If you've practiced as taught here, you can be confident that you'll win.

Kayles with more than 16 pins is winnable, too, but the larger number of pins do make it more challenging to work out safe arrangements. If you're interested in exploring the math behind Kayles further, check out wikipedia's kayles entry and Numericana's kayles post as starting points. Kayles is also covered thoroughly in John Conway's Winning Ways for your Mathematical Plays (enjoy these free excerpts!).

Who knew that there was so much to learn from Rip Van Winkle?

0

## Fairy Tales!

Published on Thursday, June 24, 2010 in , , ,

Between discussing the memorization of poetry (as well as memorizing speeches, monologues, and lyrics) and nostalgic, fun, and free learning resources with a friend recently, he brought up one of the oldest ways of teaching, learning, and memorizing that I'd completely ignored: Fairy tales!

Granted, you don't usually memorize fairy tales like you would a poem or speech. The important part is the lessons learned at the end. It's because of this that fairy tales tend to change from teller to teller, which is part of their fun. It's also a self-working mnemonic technique, as the lesson you need to remember is associated with all sorts of weird and vivid images.

As technology advanced, there were, of course, frequent efforts to re-tell these fairy tales in the new mediums. So, if you're ready to go, let's check out some of the oldest stories told in some of the most modern of ways – television!

Jim Henson's The Storyteller – This was actually a show within another show. In the show The Jim Henson Hour, the second half (this is why the playlist doesn't feature parts 1, 2, and 3 of most of the videos) would usually be dedicated to a segment simply titled The Storyteller, featuring John Hurt. The combination of Jim Henson's direction, and the depth of research into the fairy tales that are told made for a breathtaking and enjoyable experience every week!

Shelley Duvall's Faerie Tale Theatre – Yes, this is the same Shelley Duvall whom you remember from movies like The Shining and Popeye. This series featured a wide variety of directors, including Tim Burton and Francis Ford Coppola, so as to bring different attitudes to each of the 26 episodes, along with many well-known actors. They even had noted children's book's authors frequently design the sets!

Grim Tales – This British series featured exclusively on the fairy tales told by the Brothers Grimm. It's also the “edgiest” of all the series on this list. Rik Mayall would tell each story in his pajamas and bathrobe, while sitting in a chair that had paws and ostrich legs. Somehow, it all worked, but you need to experience it to see how.

Grimms Fairy Tale Classics – While employing a similar name to the previously-mention Grim Tales, this series couldn't be more different. This was a fairy tale series tailored to younger viewers. Originally from Japan, this anime-style fairy tale anthology series is instantly recognizable to Nickelodeon viewers by its memorable intro.

Long Ago and Far Away – This PBS series was hosted by James Earl Jones. It featured a wide variety of fairy tales from other countries (including several Hungarian folk tales), so it often included ones that weren't familiar to Western audiences. Probably the most recognizable episode of this show would have to be The Man Who Planted Trees.

Do yourself a favor, and sit through at least one tale from any one of the above shows.

The above links aren't exhaustive, so searching for more episodes by their above titles will help you find even more episodes.

1

## Bob Hummer's 3-Object Divination

Published on Sunday, June 20, 2010 in , , , , , , , , ,

Why do I keep coming back to Scam School videos? Because they're so often an entertaining and effective way of learning mathematical concepts.

This week, Scam School teaches Bob Hummer's 3-Object Divination. This is strangely reminiscent of 3-card monte, but with a mind-reading twist.

Watch the video below, and see if you can work out the method before watching the explanation (Stop on or before the 5:27 mark):

Were you able to work out the method? Whether or not you were, finish watching the video, and make sure you understand the method.

There are several great things about the routine. First, it's a great example of how even simple logic can be made to appear as a near-impossible feat. Second, because the logic is the method, you can (as noted in the video), apply this principle to any three objects. You could play this big and use large objects on a stage, if you so desired.

This trick was originally marketed by Bob Hummer in 1951 as "Mathematical Three-Card Monte". You can read more about the original version in Martin Gardner's book, Mathematics, Magic and Mystery. Thanks to Google Books, you can read about it online for free: Part 1, Part 2, Part 3.

Notice in Bob Hummer's original version, you don't turn around. Instead, you have them call out the objects as they're switched, then turn around. Depending on how you're presenting this feat, this touch may make it more or less impressive. Having the moves called out can make it seem more technical, while watching the moves has a more casual appearance.

Since Bob Hummer's original version of this routine, there have been some great thinkers turning their minds to this very routine. Harry Lorayne has developed a nice addition to this routine where you never turn around to examine the objects (this version can even be done over the phone!). This was originally published in Martin Gardner's Sixth Book of Mathematical Diversions from Scientific American, and is now also available in Harry Lorayne's own book, Mathematical Wizardry.

Magician Max Abrams developed a great version of this classic, but routined it as a test of the spectator's ESP. It features the interesting twist that the performer mixes the cards, yet is still engaging. It also comes across less as a puzzle, and more as a shared experience. It's called Hummeracle!, and can be found in the March 1990 issue of Genii magazine.

Take a deeper look at this great routine. It's well worth your time.

0

## Knight's Tour Videos

Published on Thursday, June 17, 2010 in , , , , ,

The Knight's Tour lessons have long been a popular section of Grey Matters. Thanks to the efforts of the people at the Mind Magician site (formerly psychicscience.org), I've been able to add videos to the lessons over there!

There are two new videos, the first of which shows how to solve the standard Knight's Tour, and the second shows the advanced version, where you learn how to let someone choose the starting and ending squares.

The board used in these videos is also available online for free, and is a wonderful instructional tool

Here's the basic version, which has also been added to the Using The Patterns tab of the Knight's Tour lessons:

Once you've practiced that approach and are comfortable with it, you can then move on to the advanced Knight's Tour. This video can also be found in the Advanced tab of the Knight's Tour lessons:

Over on the new Downloads page, you'll find several versions of the Knight's Tour you can use to practice, including my Knight's Tour+ iPhone/iPod Touch app.

For those of you who enjoy practicing the Day of the Week For Any Date feat, Mind Magician also features an excellent tool for practicing this feat, as well as an alternate approach to determining the date.

0

## Yet Still More Quick Snippets

Published on Sunday, June 13, 2010 in , , , , , , , , ,

Let's get right to the June snippets, shall we?

• My first snippet, instead of being a link, concerns Grey Matters itself. Take a look over in the rightmost column, and you'll notice some major changes. Both the feed and downloads sections are gone, replaced with links to the new Downloads page (divided up into free and commercial downloads) and Feeds/Social Links page. Having these on individual pages allowed me to greatly expand those pages, while also making them easier to maintain.

• For those of you who download and use the MAGIC Magazine Database, which currently only has issues from September 1991 to October 2009, I've posted data for November 2009 up through June 2010 here (and will continue to add new issues as they come out) in CSV format.

• If you're learning the Day of the Week For Any Date feat, there's a great new way to train for it, and it's free! Magnus Bodin, from Sweden, has developed a large amount of mp3 training files for this feat. In each individual file, a date is given, then there's a pause, then the day of the week on which that date falls is stated (the voice is computer generated, BTW).

The files are arranged in “albums” of 1,000 mp3 files. You can get the albums with 8-, 11-, 15-, 20-, and 30-second pauses, as well as in day/month/year order or month/day/year order. Living in Vegas, I've found it's handy to practice with both formats, as it's not unusual to run across people from all over the world.

This is a great tool, as you can put these files in your mp3 player or mobile device, set the device to shuffle the order in which the mp3s play, and practice working your way from the 30-second delay album down to the 8-second delay album.

Update (June 14, 2010): Magnus Bodin has just updated the files with the following changes:

1. Re-generated all files with a new algorithm to ensure that the dates are more well spread out.
2. All DMY and MDY-dates are now different, so for those of you who mix these, you will have more different dates, hopefully.
3. The inhalation pause is decreased from 5 to 4 seconds.
4. More "elite"-files provided for you speedy ones; there is now sets with a pause-length of 7,6,5,4 and even 3 seconds!
5. Now all sets contain exactly 1000 files, and not "approximately 1000".

I've talked about learning languages before, which is perhaps the ultimate memory feat. If you're truly interested in learning a language, I suggest checking out the Fluent In 3 Months blog. At that blog, you'll learn effective attitudes and approaches to learning a new language that can help you learn it quickly and easily.

• While I'm on the topic of learning a foreign language, check out Livemocha, where you can practice your skills by talking to native speakers of that language! Another fun language-learning approach is this Talking Cards game, where a regular deck of playing cards is shuffled, and then depending on which cards turn up, you have to describe or answer something in the language you're learning.

• For those of you who enjoy magic squares, check out this attention-getting presentation for a magic square! A number is given, and then the performer proceeds to write another number down on a post-it note, which is then stuck to the wall. The performer then writes another number and another number until 16 numbers in all have been written and stuck to the wall. The performer then proceeds to move the numbers around on the wall and finishes with them arranged in a magic square!

I like this approach, as it makes the creation of the magic square as fun as the revelations of the patterns are amazing! Also, if you already do a version of the magic square, such as this one, it's not difficult to adapt to this presentation.

• I'll wrap this edition of snippets with some thoughts from xkcd fans. If you've ever wondered what this particular group of geeks thinks would be cool to learn and/or memorize, you've got your answer. It's interesting how many of the things listed there are already taught here on Grey Matters.
––––––––––––––––––––––––––––––––––––––––––––––––––––––––

3 by 3 grid:

4 by 4 grid:

5 by 5 grid:

3

## Review: Magic and Mentalism of Barrie Richardson (Vols. 1-3)

Published on Thursday, June 10, 2010 in ,

Last Thursday, I received the new Barrie Richardson DVDs in the mail, and I've been spending much time since, in order to bring you this review.

Even before these DVDs were released, there were several remarks about Barrie's performance just based on L&L's preview:

The best response to these concerns came from Steve Pellegrino's sadly-missing (at this writing) Mentalist Magazine, in his article New Barrie Richardson DVDs: Pre-Review (link is cached, be patient):

If ever there was a set of L&L DVDs that are going to create a divide – this is the set! So many people are familiar with Barrie’s wonderful books and are anxious to see the material come to life – if they already haven’t started performing the material themselves.

Mentioning the up-coming release to several close friends, most had the same reaction and that was Barrie isn’t the most dynamic performer. And that is true. Here’s one quote from a magic forum:

He is very boring to watch though. I only like mentalism when it’s fast, direct, and impossible.

And this is where the divide takes place. The material on the DVDs is great. He is an incredible thinker and the material is worthy to be in any mentalist’s repertoire. But Barrie’s presentations tend to be slow. So when buying these you need to know why you’re buying these.

Are you buying these to be entertained?

Let me ask you a couple of other questions.

Are you the type of a performer who is looking to have everything handed to them and all you have to do is learn the script?

Are you the type of performer who is 100% sure about their onstage character and prefers to write their own presentations?

If you’re an amateur, just looking to be entertained with some new DVDs, you will be disappointed. If you’re a working pro that can see past the presentation on the DVD and envision their own take on it, then you will benefit from these many times over.

This is very true. If you're used to learning not only the methods but the presentations from a given set of DVDs, then you're going to miss the value of these DVDs.

Side note: How can the commenter mentioned above not consider the routine in the last 3 minutes of the preview to be fast, direct, and impossible?

The two things that stand out the most in these DVDs are Barrie Richardson's professorial style of presenting, and his ability to get great use out of the simplest of tools. The latter actually seems to be an outgrowth of the first.

Most of the routines are wrapped in a story or metaphor. Even if this isn't currently a part of your style, there are many good lessons here in using this style that you may find yourself considering this approach for some routines.

Barrie definitely likes his methods to be simple, direct, and effective. You can see in the videos that he tends towards methods and routines that work just as well for a few people as they do for a large crowd. He also tends to use the same principles and methods repeatedly and appropriately, yet is smart enough to disguise them by giving them different contexts.

A good example of Barrie's approach is the Impossible Knot Routine on volume 1. The GW Hunter Knot is known by many magicians, the majority of which don't learn its true value. If, as Rudy Coby suggests, you learn with simpler tricks, and get your audience to respond to you instead of the tricks, this is one of those effects that can be very valuable. For example, Timothy Hyde uses the Hunter Knot to reliably draw an audience.

As an aside, many people associate Barrie Richardson with mentalism, but a look at the effect descriptions will show that there's plenty of routines for both magicians and mentalists.

The methods themselves are usually first taught solo by Barrie, which is often an overview that assumes much of the knowledge that is required. After the solo teachings, Barrie is often joined by Michael Weber, where details of the method are more fully fleshed out. Often, they also discuss other possible presentation ploys, and even alternative methods!

The Bill In Lemon routine is an excellent example, where the importance of moments, appearance, and attention control are stressed. Even if you never do the Bill In Lemon, there's plenty here to learn and apply in a wide variety of effects.

Amusingly, those who don't see the kind of performance they like in the preview will most likely miss the gems in the discussions with Michael Weber that could help them make their presentations more effective and in line with their ideals!

On volume 2, the focus turns to mentalism effects. However, to think them only as mentalism is limiting, since it wouldn't be difficult to adapt many of them to magic.

In the above preview, you see Dollar Divination and Thoughts With Wings performed, both from this volume.

As you can see by now, I'm very impressed with the lessons of presentation taught on the DVD. That's why I'm not discussing individual effects here. In Second Spot, as a matter of fact, the method is almost secondary. Rather, the audience management and presentation options get more attention here, especially in the discussions with Michael Weber.

There's also a repeated emphasis on giving the routines an “everyday” feel. Sure, the happenings are magical, but they're associated with experience to give them a very realistic feel. This is only part of the true value of the story/metaphor approach used so much throughout these DVDs.

The 3rd DVD will be of special interest to Grey Matters readers, as it contain math- and memory-related routines. Often presenting such feats is a real challenge because it's all too easy to present them with an air of superiority.

There's a wide variety of approaches here that are used to remove that sting. In Quartet, they become part of the action as the cards are identified. In Zebras and the Magic Square, they're drawn in with an incomplete metaphor, which is brought full circle on after the magic square itself is done. The metaphor is so important here, even anyone who knows the same magic square method you do will have cause to enjoy it, and not feel the need to “catch” you. In the Human Movie Projector, the audience themselves provides the climax!

All this talk about metaphors and stories may sound high-minded and theoretical, but it's really very practical. I suggest the book Made To Stick for anyone who truly wants to understand what Barrie is doing.

Also, it should be noted that not even Barrie feels the need to present things this way every time. In the Memorized Time Magazine piece, he lets the feat be exactly what it sounds like: someone recalling the details of a magazine they've memorized.

It's important to note that, by the time this piece is presented, the audience should already be at ease with the performer from previous routines. Also, Barrie makes this more interesting by employing related items that aren't part of the magazine. This makes him seem less like a machine giving data, and more human. In the discussion with Michael Weber, the lessons in what NOT to do when presenting this feat are probably even more valuable that what to do!

Overall, I'd have to say that this is not a tape for beginners. If you're already developing a consistent stage persona, you're in the target audience for this tape. Even if you never use a single piece from these tapes, the lessons in presentation and thinking applied to other routines are more than worth the price of these tapes.

As a more complete look at the thinking involved, I'd also recommend his books Theater of the Mind and Act Two, as companions to the tapes.

Magic dealers should give the following test to anyone interested in these tapes: Show the footage of Michael Weber cutting up a Jerry's Nugget card box (a brand of cards that are often highly sought after and valued by card magicians). If they wince, it's a good sign that such a person would get no value from the Barrie Richardson DVDs.

1

## Werner Miller's Magic Square Puzzle #4

Published on Sunday, June 06, 2010 in , , , ,

It's Sunday, and that means it's time for the last of Werner Miller's devious magic square puzzles!

I'd like to thank Werner Miller publicly for very generously devising these puzzles, and letting me share them with you. Next Sunday, Grey Matters will return to its regular blog posts, and the answer to this puzzle will appear at the end.

For those who are new, here are the basic rules of the puzzle:

You're given the same set of 4 starting numbers grouped together in similar locations in a 3 by 3, 4 by 4, and 5 by 5 grids. The object is to fill out the grids with other numbers in such a way that the following conditions are satisfied when the grid is completed:

1) Only positive whole numbers are used.

2) No number is duplicated in a single grid (the same number may be used once in each of the 3 grids, however).

3) Each row, each column, and both diagonals of a single grid must total the same sum. All 3 grids in a puzzle, however, are not required to have the same sum (and usually won't). In other words, each grid must be a magic square, but all 3 grids do not have to have the same magic square total.

4) Puzzles will be posted here each Sunday, with the answers to a given puzzle being made available the following Sunday.

3 by 3 grid:

4 by 4 grid:

5 by 5 grid:

Can you get the answers to these magic square puzzles? If you can solve it before next Sunday, let me know in the comments! You can either describe your solution there, as best as you can, or link to a graphic of your solution.
––––––––––––––––––––––––––––––––––––––––––––––––––––––––

3 by 3 grid:

4 by 4 grid:

5 by 5 grid:

0

## Scam School Meets Grey Matters

Published on Thursday, June 03, 2010 in , , , , , ,

Scam School has taught some great variations of Nim in the past: Nim (with matches), Advanced Nim (with coins), and 31 (with cards). What happens when Grey Matters meets Scam School? Naturally, we get rid of the objects, and make Nim a completely mental game!

To be fair, I didn't create this. The earliest reference I can find to Calendar Nim is this 1981 classroom guide, which includes a computer program that plays the game. I'm sure the game goes back much further than this, but I'm unable to find any references before that (If you have any such references, please leave a note about them in the comments!).

Back in March, I e-mailed Brian Brushwood with this scam, and he's made it the focus of this week's episode, along with a 1-100 version submitted by Lee Blackburn (Lee, if you'd like me to add a link to your site/blog/twitter/etc, send me the link!). Here is the episode itself:

Calendar Nim was also written up in the May 1999 issue of MAGIC Magazine as Y2 Kon in Bob Farmer's Flim-Flam column. Shortly after that, Mark Farrar created a simple online Javascript version of the game. The computer will always win in this version, so it's a good way to feel the frustration of being the mark.

BONUS SCAM: Not mentioned in the video is the fact that you can also do Calendar Nim backwards, starting on December 31st, and trying to be the first to land on January 1st. The same rules are in place: You can change the month or the date, but not both, and you can't use any fake dates. This version was also written up by Bob Farmer, in the June 1999 issue of MAGIC Magazine.

Strangely, this is actually easier than the forward version. The key dates are as follows: Dec. 12th, Nov. 11th, Oct. 10th, Sep. 9th, Aug. 8th, July 7th, June 6th, May 5th, April 4th, March 3rd, Feb. 2nd, and Jan. 1st. Notice that the key dates are simply the month numbers themselves (December is the 12th month, so the 12th is your key date for December, and so on).

Mark Farrar also created an online version of the backwards game, as well. Again, the computer is going to win this version, so prepare to lose this one, as well.

The 1-100 version of the scam also appears in The Chrysalis of a Polymath, as in the mental “giveaway” chapter, which has other great feats you can perform for, and teach to, other people.

3

## Free Online Mnemonic Sites

Published on Thursday, June 03, 2010 in , , ,

I talk a lot about memory and mnemonics on here, but where do you go to find specific mnemonics? In this post, I'll share some great (and free!) online resources where you can find mnemonics for just about anything!

Mnemonic Look-up Sites

These are great sites for established mnemonics:

Amanda's Mnemonics Page (Backup link) – Alas, this once great site exists only in the web archive now, but the mnemonics still work!

Forget Knot – There are fewer mnemonics on this site that many of the others, but it's still a good resource.

Medical Mnemonics – Studying medicine? Here is the single best source for medical mnemonics, including the more obscure ones.

Mnemonic Device.EU – This is an excellent site: cleanly designed, and the mnemonics are easy to get to, and even to submit.

Mnemonic Devices – This site, which offers some mnemonics not common to many of the others, is also available in Dutch, French, German, and Spanish!

Mnemonic Dictionary – This is a site focused exclusively on mnemonics for vocabulary words. The mnemonics are usually to help remember the meanings of the words, but you can also find the occasional spelling and usage mnemonics, as well.

Mnemonics/Memoria Technica – Sure, it's an old-fashioned frame-based site, but it offers direct access to categories, and many of the mnemonics are illustrated, where needed.

My Dear Aunt Sally – This site, whose name comes from a mnemonic for the order of mathematical operations, is set up as a search engine. It also enables you to easily add your own mnemonics.

Project HappyChild Mnemonics – This is a small, but useful collection of the more common mnemonics.

Think-a-Link – Think-a-Link is a social mnemonic site that allows you to submit your own mnemonics, as well as rate those of others!

Wikipedia Mnemonics – As with all things Wikipedia, this is a growing collection of mnemonics, and a good place to look for some of the more obscure ones. It also has the unusual feature that the mnemonics themselves are listed, as opposed to what their subject matter.

Mnemonic Generators

Sometimes, there are no established mnemonics for what you want to remember (for example, this blog post). That's where these handy mnemonic-creation tools can come in handy:

Chaucery Fun Mnemonic Generator – The generates mnemonics for 4-digit numbers only, mainly using the number of letters in a word as a reminder, such as “they fight american lobster” (4 letters, then 5 letters, then 8 letters, then 7 letters) for 4587. Sometimes, they use words like “nun” (none) or “not” (naught) for 0, and “solo” or “lone“ for 1.

JogLab – Here's a great tool for automatically generating acrostic mnemonics with up to 14 letters (and more, if you break up the required letter sets. Here's a video that gives you the basic idea of JogLab:

Mnemonicizer: The Mnemonic Device Device – NASA posted this simple and free tool to help people develop their own original acrostic mnemonics. It's more basic than JogLab (above), but still quite useful.

PhoneSpell – Trying to remember someone's phone number? Put it in here, and see what, if anything your phone number spells!

Rememberg – Like the Chaucery Fun Mnemonic Generator above, this one helps you remember numbers. Rememberg has two advantages though: It can handle more than just 4-digit numbers, and it generates the mnemonics in both the “count” system (again, like the Chaucery Fun Mnemonic Generator), and the Peg/Major System!

Spacefem's Mnemonics Making Page – The simplest of the acrostic mnemonic generators in this post, it simply asks you to enter letters required, and then generate random, yet gramatically correct, sentences. For example, entering PiGuy yielded “Plaid Igloos Grow Ubiquitous Yolks”, “Pristine Islands Grab Unintelligent Yaks”, and many others.