Post some multiplayer games that you played and enjoyed particularly.
Goldeneye 007 (N64)
007 Agent Under Fire (PS2)
Red Dead Revolver (PS2)
Time Splitters Future Perfect (PS2)
Territory Wars Online (Internet Flash Game)
Tony Hawk Pro Skater 3 (PS2)
Tony Hawk Project 8 (PS2)
Gran Turismo 4 (PS2)
Super Smash Bros. Brawl (Wii)
Need for Speed 3: Hot Pursuit (PS)
Ratchet: Deadlocked (PS2)
Soul Calibur II (PS2)
The Bouncer (PS2)
Those are a few of my favorite I'll edit in the systems their on later.
(Edit: I added all the consoles for the games. Be it most games are on a few consoles but I only listed the versions of the game that I played because I'm not 100% as to all the consoles the games were available on)