What Steam Game Have You Spent The Most Hours Playing?

well "TECHNICALLY" tf2 but i dont really like it, thats just idling
my most played game is gmod and i really like it, has SO MUCH different stuff... followed closely by gta iv and duke nukem forever

TF2 375 HRS
Garrys Mod 126 HRS
GTA IV 102 HRS
DNF 97 HRS

Counter Strike 1.6 with around 150 hours, it's also the reason I joined steam. Haven't really played it much since I got it on Steam, but I probably had nearly 1000 hours on the non-steam versions.

It will probably change soon, when I get a slightly better PC and some more free time.

Titan Quest: Immortal Throne - 338 hours

dota 2 up to 330, but I also played half-life deathmatch a lot... but it was long ago and I don't know why, It says I played less...

Counter strike source almost 1000 hours

Killing Floor 222 hours.

Audiosurf... 290 hours on record (another at least 100 hours offline due to lack of an internet connection.)

TF2 4948 hours (1000-1500 hours idle and trading server)

and 2. Rift (1000) 3. Dungeon Defenders (1000)

Killing Floor at 163 hours
TF2 at 160 hours
And L4D2 at 136 hours

TF2 450hrs (idling)
Killing Floor 150hrs
CSGO and CK2 100hrs

Those are really addicting games..

Spiral Knights with ~360 hours.

Star Trek Onlie 860 hours until now

CS:GO 71 hours!
If only I had the time, there are so many other games that I want to play.

Team fortress 2 3200+ hours

TF2...I think...

Edit: No wait...it's MW3 320 hours. >:|

Dota 2, about 500 hours

CoD Modern Warfare 2 = 475 hrs

Dota 2 - 850h

gmod, BO2, MW2, Civ 5, XCOM, Warband:0

Spiral Knights

Dark souls 213 hours. The Binding of Isaac is close 2nd with 208.

I have 325.8 hours in The Binding of Isaac. I beat it (Platinum God) in like 200, I just have fun playing.

Played TF2 for the first time a few days ago and I get the feeling I'm going to end up putting a lot of time into that...

Saints Row: The Third
85.1 hrs

Plants vs. Zombies: Game of the Year 35.9 hrs on record
I beat it completely with all achievements. So,
Dota 2 32.4 hrs on record
is catching up.

Dungeon Defenders 227h