The Raust is a place in Halo 3 where one is able to snipe the hell out of all sentient n00bz on the map, while still retaining the ability to defend oneself from close range with a shotgun blast to the face of any opponent.
Playing in the Raust for too long can induce tears of joy from the absolute pwnage going down.
Basically, its Cheezus. Ham'dullah for the Raust.
Jason: Rause, you just got 20 kills on that map, which is like, what, 2x what the first place player on the other team got. Where were you that whole game?
Rause: In the Raust, of course, Cheezus.