I usually get 5.5-7 hrs during the week. Can't fall asleep until 12pm - 1:30am and then up at 7am. Ocassionally, if I have a deadline at work, been know to stay up 'till 2-3am.
I always say, once you have kids you learn how little sleep you can survive on! If I go too many nights on the 5.5hr side though, I've been know to take a Tylenol PM to help me crash at 10pm. I'm naturally a night owl, so the later it is in the night, the more awake I seem to be!