Shooters: I've always been a huge Tribes fan. My pals and I would pass around my Tribes disk and get other people hooked. It was like a freakin virus! UT2k4 comes close to matching the fun of a good old Tribes skirmish. If Vengance wasn't so freakin buggy, it would be my favorite game.
RPG: Fallout and Fallout 2 are simply unmatched in the fun factor, and their open-ended style allows you to play the game any way you want to. I don't know how many times I'd just play the game to wipe out all living creatures in every single town. Then the next day, I'd save every single town when playing it again. Since those games, only KOTOR and KOTOR2 have come close to allowing me to be as evil or as good as I want to be in a game.
Strategy: X-Com. Yeah, it's old. But once you get the blaster cannon, nothing is as satisfying as taking a downed mothership by raiding it from the top down with powered flight-suits and plasma rifles. Since then, some of the UFO:Aftershock games have upgraded the graphics without losing the fun.
MMO: City of Heroes/Villains. I haven't even gone past lvl 20 in the 2 years I've been playing, but I can't help it! The character creator is so freakin fun that the game is like an extra feature, not the other way around. I gave up WOW to play the City series. I haven't looked back yet.
Console Game: Legend of Zelda: Twilight Princess for the Wii. Best Wii game out there yet.
Exit, pursued by a bear.
- William Shakespeare