Recently with GTA V, been playing it so much and well I spent around 8-10 hours playing it straight. My eyes were bloodshot, pretty sure people thought I was doing drugs
Maybe 5 hours for me. Im getting older now (almost 38) so I dont like to play so long any more. A good two or three hour session is enough these days. Saying that, my total play time on EDF4 clocked in at 118hours today. My son ad I have played it 105times now and still love it.
Back in the day, 12-14 hs sessions of Smash Bros. 64, Pokemon Stadium, Mario Party, Perfect Dark, Goldeneye, all nighters with a couple of friends. Then, usually 8 hs sessions on weekends playing Ocarina of Time or Majora's Mask, good old days. Starcraft on N64, longest match 10 hs with my cousin.
Over the summer I played Tales of Xillia for around 14 hours (included restroom brakes and snack brakes.)
The day Halo: Reach came out, I think I hit 9hr. Once I start getting into double digits, my brain becomes too fried and I just can't enjoy the game anymore.
I think the only game I've literally played all day was Zelda: Twilight Princess for Gamecube when it first came out. Got it in the morning, and when I finally decided to call it quits, my playtime was 12 hours. ...It was a little disturbing, actually.
I wish I had the time you guys have The max I'm been able to squeeze in is 1-2 hours. It takes me months to beat a game.