Over at Boing Boing, Mark Frauenfelder discusses a dice game that seems fair, but is actually in your favor. Done correctly, you can always select a die that will beat your opponent on 2 out of 3 rolls, over the long run!

This is the result of the design of the dice themselves. As Mark points out, there is a wonderful explanation of the mathematics by Ivar Peterson available online. If you're more interested in getting to the game itself, the dice themselves are available from Grand Illusions, in both a numbered version (this is the set described in the lined article) and a more traditional spotted version.

What's that? You want to pull this con without using suspicious and unfamiliar dice? Mark has an answer for that, as well. In this Boing Boing entry, he describes a similar con game that's played with regular coins.

If you like these types of cons, I highly suggest you seek out back issues of MAGIC and Genii that feature Bob Farmer's Flim-Flam column. In each column, Mr. Farmer presents various con games, and discusses the principles behind them in depth. One of my favorite cons is one that seems to be based on blackjack, but, unbeknownst to your opponent, is actually a well-disguised game of Tic-Tac-Toe played on a magic square!

These articles make for an interesting read for two reasons. First, the simple nature of these games opens up a surprising lesson in mathematics. Second, how often do you learn about con games from a Mark?