I remember falling asleep once with my iPod still on, and I slept for like 5 hours and when I woke up the music was still playing. Prob doesn't count but still.
Also, as a kid I think I remember listening to some techno song for like 3 hours, and danced like a stroke victim. I was eight, okay.
Also, if you remember that one "The Great Trip" loop I made I'm listening to it now