I do 6-7, usually, and I have a lot of troubles going to sleep, so I have a very specific, fairly strict bedtime routine. Alarm at eleven, practice guitar for an hour, brush teeth, read programming books in bed till I'm sleepy, up at 8:30. (I'm not dutiful in following the alarms, they just remind me what time it is.) this routine is very important in maintaining a steady sleep wake cycle in the face of no time clock and many responsibilities.