So far this year, not many, I have been playing some older games.
Diner Dash: Flo Through Time (Bought it for my sister, pretty nice game. Also, very addictive.)
Dungeon Siege 2 (For the who-the-hell-knows time, was interested again at the beginning, but got pretty boring as I was moving towards the end.)
Dungeon Siege 2: Broken World (For the first time, got a little boring in the end, my character was maxed out, it wasn't fun doing the same stuff again and again.)
Half Life 2 / EP1 / EP2 (Finished it again, three times in the last 4 or 5 months. It never bored me. Might start playing it again in the next month.)
Rise of Nations (Yeah, I conquered the world. Again.)

I smacked some nasty booty on this
http://www.wegame.com/watch/Mack_The_Knife/
First time player, Scored Number one, and got The Olympian Achievement.

just finished the guild. At least as much as I could finish open ended game.
gets a bit repetitive after a while
Will update list a bit later.

I finally sat down this weekend and played through Mega Man 9. :D!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1
I also put 3 hours total into Noby Noby Boy. Should we consider that complete? I don't know. There's no ending to it...just dicking around, like flOw, but I can say that Noby Noby Boy rules! Flower is next!
Still slowly playing through Descent. A level every few days...

I know I have finished more games, but the only game I can recall right now is Call of Duty World at War.
EDIT:
Mirror's Edge. Twice. In 4 days.

Just finished mod for HL2. Minevra: Metastasis. it is like a small game. bigger than Episodes.
updated the list and if there are any mistakes (spelling, forgot about something) let me know.

You forgot my CoD WaW >:(

sorry sorry :)
corrected.

Just completed mars matrix on the good ol dreamcast XD what a bastardly hard game!

I finished Perimeter 2: New Earth. Interesting, but quite flawed. Fun enough that I actually bothered to complete it, though.

Just finished Red Alert 1. Allied side (Soviets' missions I beat few weeks ago).
I am kinda disappointed with final mission. Didn't need to use chronosphere nor navy. Just helicopters. Great game.

I liked betraying my people to the Kuei-jin and being fed to the fish for it. My kind of ending.

I just finished YHTBTR.
Great game I really recommend it.
It is 2d platform available for free on the web. Ol' school platform game. The boss is quite challenging. But there are walkthroughs on the web if anyone has troubles with it.

I have finish final fantasy crystal chronicle on gc

Just finished Eets. Great puzzle-platform game.