What games are cool for parties?

[Thatguyky]

Saints Row :The Third
Smash Brothers Brawl
Left 4 Dead 1 or 2
Any Mario Party Game
Music Games (Rock Band,Guitar Hero, Ect.)

Left 4 Dead and Brawl are my favorites. It's always interesting to see how different people freak out/react to the pressure in L4D.

 

[Funky Flump]

I'd go for some Guitar Hero/Rock Band if you have them, a whole band is amazing fun!

Fighting games are quite good too, Street fighter and the like, Smash Brothers.

They are my recommendations!

 

[Cowabungaa]

Hotseat Worms is pure awesome, though it gets rather difficult when the group gets too big.