Unreal Tournament 3 and Ageia PhysX
 

Unreal Tournament is an excellent game and there's no doubt in my mind that it'll be the backbone of PC multiplayer gaming for a fair old while -- alongside Team Fortress 2, of course. Frankly, it knocks Enemy Territory: Quake Wars out of the water like the limp fish it is. Then it beats it to death with something embarrassing and probably slightly rude. Fill in the blank for yourself, you filthy perverts.