I think 40 hours. It was when I was like twelve. I had a new friend, he had just bought a new Ps2 game, and his basement was awesome and he had this rack full of snacks and chips and we devoured them in this underground setting while killing zombies. Definitely worth it. Then I went home and I slept for a very, very long time.
I was awake over 40 hours once. I don't know how I did it but one day I woke up late in the afternoon and wasn't tired at all in the evening. Then I decided to watch movies all night and the next day was midsummer (it's the most celebrated holiday apart from Christmas here.) So, again, I stayed up all night and went to sleep in the morning. The weirdest thing is I didn't even feel too tired when I had been awake for almost 40 hours but when I finally went to bed I fell asleep immediately. I guess coffee and celebrating kept me going.