PC: Diablo (this seems to be a common first online game for many in this thread). I used to be one of those douchebags on battle.net who would PK people for shits and giggles.
Console: Uno (XBLA). I didn't own a Dreamcast or original Xbox. And I never played online with the PS2. Most people I know who had a PS2 didn't because you had to be a network adapter to do so. I have a network-ready slim PS2 but never played online with it.







