Super Mario Bros. (the original, on a good day i can play through the entire game in about 15-20 mins no warps... and yes i realize speedruns destroy that but it's fun to kill time)
Half Life 1 & 2 including mods (600+ hours on
TF2 alone)
Diablo 2 (played for almost 6 years... stole my damn life)
NFL Blitz 2000 for playstation (played over 400 games)
WWF Smackdown for ps2 (had epic 30 punch/counter battles with friends)
Quake 2 for playstation (devoted a friends birthday party to playing this game 2v2 splitscreen score of about 200 - 60 lollll)
Quake 3 Arena (played ctf on the space maps for hours on end)
Perfect Dark for N64 (sentry guns ftw... raping teams of elite bots with friends was downright amazing)
Timesplitters for PS2 (dual shotgun headshots down the street on anything that moved... changed so that uzis ruled the sequel... which was lame as shit as they require no skill.)
WoW (played for about a year before I decided that 2 70s, a 60 and countless other 40s that were always being remade was taking up too much time... only to move on to
TF2 >.<)
Duke Nukem 3D, Starcraft, Warcraft and Red Alert ate up the rest of my time, but that would make 14 now wouldn't it.