Another Humble Indie Bundle is going on for another 12 days (as of this post):
The featured game is Frozen Synapse, which can pretty much run on anything 2004 and after. Its an awesome game, think X-COM had babies with Rainbow Six and TRON. Yes, all three of them. Had a baby.
If you buy the game for above the average amount (above $5 as of this post), you also get: Trine, Shadowgrounds, Shadowgrounds: Survivor, Splot (preorder), and Jack Claw (prototype)...which was the previous Humble Bundle.
All the money you spend goes towards charity, and you can spread the amount between any of the developers and the supported charities.