Good for you.
Still got monkey island 3 lying around somewhere.

Heh, Aether.

Just finished Penumbra: Black Plague good, scary frustrating this game got it all.

Just finish Freespace : the great War from GOG !!

This year so far just Fallout 3 with OA.

oh my. Big updated this time. Added two more users to our little list.
I finished Nox as a wizard. ATM I am replaying as conjurer. I simply love this game and I have finished it as many times as fallout 2.

Finally finished a game:
Fallout 3.
I don't have any DLCs yet, since I don't have GfWLive.
Edit: I forgot to mention my time played: 160 hours.

Beat S.T.A.L.K.E.R. Finally. That game was brutal, but totally worth it.
I gave up on Jade Empire despite being within the last couple of hours of the game. Just way too frustrating.
Now I'm working through Freespace (original) and Mount and Blade in-between heavy gaming sessions of TF2.

tetris attack Gameboy
and tetris attack on hard, going to try very hard in a few days.

Finished "Fitness Dash" few days ago.

Not a ton so far...
Fallout 3 - Operation Anchorage: Can't really list the main game, as I beat that at least twice last year... actually, guess I got a third char to level 20 this year, does that count? Anyway, finished Anchorage in a few hours, as it slowed my computer to an absolute crawl - we're talking 2 fps at some points, where the original game never lagged at all. Overall, it was okay, not that impressive - bonus gear was all right, but nothing mind-blowing (especially compared to all of the user-created mods I had already loaded).
Dawn of War II - a radical departure from its predecessors (and my favorites) Dark Crusade and Soulstorm. It was still interesting to play through the single-player campaign, but I began replaying Dark Crusade afterwards and realizing how much more I enjoyed it. Honestly, DoWII is fun, but very small-scale, and at no point do you ever get the enjoyment of building up a powerful, awe-inspiring army and crushing countless enemies under your treads. Even the dreadnought seemed incredibly nerfed, as did the "terminator" armor. That being said, though, there were a couple of very fun missions, as well as the opportunity, every so often, for some truly impressive heroics.

This is truly a sad list, as it doesn't include any of the games I finished over winter break, but I will not let that phase me:
Prince of Persia: Definitely better than the last two games, but I started to have to force myself to finish it before I went back to college. It seemed a little repetitive near the end, but I guess that's one of the downsides of an open-world like that.
Sam and Max: Season 2. Had a terrific time with this; I had been looking forward to playing it over winter break and finally got around to it. Excellent.
King's Quest 1 VGA (AGDI Remake): Sat down and played this all the way through in about 15 mintues for a perfect score. Just for kicks.

Wow.
This thread really made me think.
Although I have started a LOT of games, I have only finished one of them (and probably wont go back to most that I started):
Mirror's Edge is the only game I have finished.
:(
Edit:
Just finished Duke3d as well as Max Payne.

Since my last post, completed games include: In Cold Blood, Beneath a Steel Sky, Simon the Sorcorer 1 & 2, Freespace 1, World of Goo, Shogo:MAD & Descent 3.

Heroes of might and magic 5 tribes of the east. Such a crappy ending for how many hours I sunk into that series, I think it was at least 250hours to get through all 3 of them. Gameplay luckily more then made up for it.