6. Grand Theft Auto III (PS2)
The first two Grand Theft Auto games were pretty controversial and garnered their fair share of bad press, but the series didn't truly become something major until the release of this game. The move to 3D greatly changed the dynamic of the game and made it far more enjoyable, even though the basic structure wasn't really that different from the previous games. Of course one of the great things about GTA is that you don't even need to progress through any missions if you don't feel like it at that particular moment, you can just mess around in the city creating chaos or finding things to jump off in your car. Then there's the various radio stations which were always entertaining, particularly the talk show hosted by Lazlow. This stands out amongst later GTA games for me because it was the moment the series changed, and it was a change for the better.