Direct2Drive has a big 5th anniversary sale going right now over a 5 week period, with 10+ games available each week each for $5. This week is action games, but coming up are RPG/MMO, Indie, and War games. They're not announcing which games will be available in the coming weeks, but there are some good games there right now (such as Bioshock) so check it out, a lot of these games are definitely worth the $5. There are also some additional $5 games available at the bottom of the page.  One question: When D2D turns 10, will the games be $10?

http://www.direct2drive.com/d2dturns5