FilePlanet recently compiled a list of ten free games which surprisingly consists of mainly FPSes, mods and MMOs. [source: xii games]

1. F.E.A.R. Combat
2. Puzzle Pirates
3. Future Pinball
4. Beyond the Red Line (Demo)
5. Penumbra
6. America's Army
7. Anarchy Online
8. Trackmania Nations
9. World of Padman
10. Linus Bruckman