Currently playing:
MechWarrior: Online - Free -
http://www.mwomercs.com
Natural Selection 2 - $25 -
http://store.steampowered.com/app/4920/
Civilization 5 - $50 w/ all xpacs -
http://store.steampowered.com/app/4920/
Also have a few SP games I'm slowing meandering through, Sleeping Dogs, Far Cry 3, Hitman:Absolution.
I also pre-ordered Aliens: CM but haven't touched it. There are 2 huge projects by fans to overhaul the game and make it not total crap, so I'm just kinda twiddling my thumbs until they are done.