The first weekend that Super Mario 3 was released. Friday at 4:30 to Sunday at 8:00. Five hours for sleep and food. I've never been so tired at school.
It's a toss-up between The Elder Scrolls V: Skyrim or Minecraft. I didn't time myself, but I played both for a good 12 - 13 hours strait before shutting off my console/computer.
I believe it was 13 hours of playing One Piece: Unlimited Adventure on the Wii... I didn't stop for food or anything... I think that was the longest single time playing a video game with no breaks that I've ever done, if I remember correctly.
It's a bit fuzzy, but I'm going to say it was about eight or so hours on 'Sly 2: Band of Thieves' back in the day.
Nowadays when I play games I'm on average about 1 1/2 - 2 hours a session.
I think either yesterday or Saturday I played Minecraft with some close friends for about 7 and a half hours. That's the most I've ever played in one sitting.
The day before Super Smash Bros. Brawl came out, 3 of my friends and I played Melee for about 15 hours. Then we went to the midnight release for Brawl, and played Brawl for 19 more hours until one of us passed out. Very good times.
I remember back in the day when Call of Duty 4 was released and me and a bunch of friends were playing in private match playing a made up game mode which was called "Mike Myers"and we were playing from like 10:00pm till 3:00 am. This is back when Call of Duty used to be good am not a fan no more but I still love this game!