Think the longest time i've ever slept was about 18 hours or something, that was right after i had set my personal record by staying up for 53 hours straight playing video games at a gaming convention me and my gaming-society arranged here where i live (Örebro, Sweden).
I think i broke like 4 personal records at that convention

, longest sleep, longest uhm..awake?, then longest gaming session at 1 machine (NES for almost 20 hours), that and i managed to play through loads of games i had been wanting to try out but never gotten the chance to, for example some Sega games, which is the fourth personal achievement, i finished a Sega game ^^ (i didnt own Sega when i was young, only Commodore64/NES)