Xbox 360 game help

so i can't just go and buy all sorts of games, so i'm looking for something super awesome that is 2+ player coop friendly, split screen or top down as long as you 2+ people can play at the same time, online or offline.

what do you guys play?

edit- haha! wrong forum! i suck.

Resident Evil 5 comes out in February and might have what you're looking for.

Look into Left 4 Dead as well.

Castle Crashers is fucking good co-op! and it only costs 15$ on xbl arcade. dont call it a bargain title though.