In another thread, Bruno commented that my "extra" hours of sleep are a luxury. It just got me to wondering about how much sleep people get and what factors determine the amount of time. So, if you like, please share with us (or me) how much sleep you get per night and why. Feel free to include any other info might be relevant.

I'm a grad student in education, so student teaching determines my wakeup time. I am fortunate insofar as classes at the school at which I student teach don't start until 8:30, but I get there at 8 to help set up and review the day's plans. I try to get to bed by 10:30, but that typically turns into 11. First alarm in the morning is 6:40, but feet touchdown at 7:00.

So, in summary:
Grad student/student teaching
2300-0700