Somewhere in the 24-30 hour ranges back when I was into DAoC. Non-MMO, probably 10-12 hours when significant releases hit for me. I tend to take release day off from work to play.

13 hours straight on GTA Online. I was in a party and I saw people go to take a nap and then near the end of my session join in again xD.

I think bloodborne was the recent one

I one sitting, I think I played Hyrule Warriors or Age of Empires 2 for about 6 hours

I do not know exactly. If I was going to take a shot I would say 18-20 hours

I don't remember exactly how long it was but it was definitely Civilization. Just one more turn always means another 1000 turns.

skyward sword, that Sunday I played like 11 hours.

20 hours. The 100 fight in Pokemon Colosseum was it. Never did it again. The prize of those starters was not worth those hours.

I finished Bioshock Infinite in a single 12 hour sitting.

Once I played TF2 with some friends for about 8 hours straight with food-breaks and such, but I don't recall doign stuff like that very often :P