My favorite multiplayer mode of all time is Virus for the TimeSpitters series. Watching a horde of zombies/robots/monkies engulfed in green flames coming after you is a terrifying experience. But then watching as they fall into your mine trap is a beautiful thing. 
I also loved Assault from TimeSplitters. Especially defending. Sitting in a corner awaiting the upcoming horde with the minigun: priceless.
I also enjoyed Man with the Golden Gun from GoldenEye. Trying to take down the Golden Gun owner was a trial in patience and teamwork. 
Fun times.








