July's snippets are here, and they're full of free mathematical goodies!

• Marcus du Sautoy, whom you may remember from his BBC series, The Story of Maths, has definitely been keeping busy. Besides that documentary, you can find his 10-part podcast series A Brief History of Mathematics available for free via the BBC (or, strangely, as an audiobook for sale). This is a great introduction to the giants of mathematical history.

You can also see him lecture for free about symmetry on TED, or about prime numbers at Hebrew University (via YouTube).

• I've talked about game theory recently, yet I only recently ran across a great tool for studying it. Gambit is a free game theory analysis program that runs on Windows, OS X, and Linux. There are two excellent and simple tutorials available on the site (available as both Flash movies and PDF documents) to get you started. It makes a wonderful companion tool to game theory courses, such as Game Theory 101 (free via YouTube), Ben Polak's Game Theory course at Yale (free via Yale, YouTube, or iTunes, course documents available at Yale link). I first learned about this while watching The Teaching Company's game theory course, Games People Play, which is also an excellent introduction to the field.

• Speaking of unusual calculators, iOS mobile device users should check out the free Magical Calculator app. Instead of just being a standard calculator app, you can prepare it with your own custom formulas and inputs (such as those for interest on loans or physics equations), and then you'll always have your own handy custom calculator ready! If you're familiar with InstaCalc website from BetterExplained, this is basically the same idea turned into an app.

Speaking of freebies, I'll have a very special one (non-mathematical) for you in Thursday's post!