Tend to get about 5 - 6 hours a night. I'd like to say this works for me but I frequently find myself dozing off of an evening but it's entirely random.
I seem to have a bit of a reputation for being able to fall asleep suddenly. I'm very good at sleeping as a passenger in a car and buses send me to sleep very quickly as well. Trains not quite as much but I can still dose off if my mind isn't occupied. Also have a bit of a rep for falling asleep in meetings and briefings at work. I have a sneaking suspicion that it's temperature related (if it's too hot I doze off). This wouldn't be quite so bad if I didn't have an apparently epic line in snoring going on.
Despite all that, I seem to have a damnably effective internal alarm clock that wakes me up about 6. At weekends I stay in bed till 7 or 8 or even later mainly out of sheer bloody mindedness. It's the weekend and WILL have a lie in.
Tend to officially got to bed between 11 and 12 pm and my alarm goes off at 6:15. If I go to bed earlier I just seem to either stay awake until I would have gone to bed normally anyway or otherwise my wakeup time just time shifts to the appropriate time the following day.