Currently Online 
My #21 is BioShock.
Designed with elements of survival-horror games and role-playing games, BioShock is a first-person shooter that truly transcends its genre. Players control Jack, an unlucky man whose passenger plane crashes over the Atlantic Ocean. In a nearby submarine bay he discovers passage to Rapture, a hidden city beneath the waves. Once there, Jack encounters the twisted and gruesome inhabitants of Rapture, who stop at nothing to eliminate him. Jack can interact with almost everything in the underwater metropolis, including enemies, containers, machines, and audio diaries, scattered throughout the city. In Rapture, players can upgrade weapons and create custom ammunition; they can also alter Jack’s very genetic code, infusing superhuman powers into his body in the process.
