A while back I came across this game called World of Goo that turned out to be well worth the $20 I paid for it. Now it is part of a special deal with 4 other games where you can name your price. As part of other indie packs, I already own two copies of World of Goo and one of Gish. I’m definitely going to check out the other 3 games. Proceeds go toward developers or charity depending on how you want to split it up. The sale ends 5/10/10
–update–
If you missed the deal, most of the games have now gone open source! Check out Aquaria, Gish, Penumbra, and Lugaru!