About.com, Video Game Cheats
Offering cheat codes, tips, cheats, tricks, frequently asked questions, cheats, codes, and walkthroughs for PC games and consoles including Xbox, Xbox 360, PlayStation, PS2, PS3, PSP, GameCube, Gameboy Advanced and all other major consoles and handheld systems.
http://vgstrategies.about.com/

Every Video Game
Play all the old Nintendo video games you grew up with - online and free.
http://www.everyvideogame.com/