I used to sleep at around 11pm (and sometimes 10 or 9, if I'm extremely tired), but nowadays, it's all pretty random for me. One night, it'd be 12am; another night, it would be 3; on the next, it would be 9pm. Usually, I wind up waking up after about 2 hours only. Though, I do make up for it during daytime by taking naps. =) Wish I could go back to my old sleeping schedule, but... I don't know. I've gotten used to this, and am pretty comfortable.