About five hours a night. I go to bed most nights at a ridiculous time -- usually 9:30-10:00pm -- and get up between 3 and 4am and get cracking. Before my most recent kids I used to go 36-48 hours at a time without sleep, then crash for 9-12 hours, but I needed to get on a more regular schedule with them around. Kids' energy demands are spectacular, especially when you're close enough to forty to hit the goal line just by falling down.
Frank