The Humble Indie Bundle (pay what you want for five awesome indie games)
Get it! There’s some fantastic games there, you can pay what you like (I slapped down 30USD, but you don’t event have to pay that much), and the money goes to two good causes. And did I mention that all the games run on Linux, MacOS, and Windows? They do! As of now, the offer’s open for another seven hours and forty-five minutes.