-BF Series
-COD Series
-Spec Ops
-Counter Strike ( sometimes )
-Team Fortress 2 ( rarely)
-Dragon Age series ( almost always! )
-Borderland series ( rarely )
-Batman series ( occasionally )
Yep, I'm an avid Steam gamer. Around 125 games on there at the last count. I also have the unfortunate pleasure of having to use Origin for BF3/BF4 too. And Uplay for WatchDogs and Far Cry 3.
Well, I have over 100 on Steam and about 25-30 installs, including old 3.5 disk DOS games, CDs, Atari 2600, 800, ST emulators, etc.
Mostly in first-person shooters. Favorites?
Batman Series (3)
Assassin's Creed (2)
BioShock (2)
Crysis (2)
Dark Souls
Dead Space (tense!!!)
FarCry (2)
Hitman (2)
Mass Effect (2)
Max Payne (all 3)
Metro 2033
Saints (3)
GTA (4)
Left4Dead (2)
Then a bunch of car racing (Grid, NFS (3), etc)
Here's a video of 100 of my games. Most are on Steam (gotta love autopatching)