If you like Diablo, you like Torchlight. It's a great game with very similair mechanics to the good old Hack'N'Slashs. The only thing this game is missing is coop, and a little birdie told me that is just around the corner.

Team Fortress 2 is probably the most polished mutliplayer game out there. Even though every class is played in a complete different way, you can choose any class and get just as many points as any other. The ability to unlock clothing, weapons, and what not keeps most people hooked in for a long time. Oh yeah, and it's hilarious.

Jedi Knight Academy is my favorite Star Wars game of all time. This is a truly underrated game that has the BEST saber combat out there. The single player is decent, but the real fun to be had is in multiplayer. Don't worry about not finding any games, because Academy still has a suprising large following even today.