I'm another person that needs at least 7 hours of sleep, preferably 8. In college I always had 8 am classes, so I went to bed anywhere between 10:30 and midnight. It really depended on what was going on with my sorority. On weekends, it varied, but on average I would hit the sack around 1 or 2 am.
Now I'm fresh outta college and in the real world, where I have a job that requires me to show up by 7 am. I go to bed around 10 usually now. On weekends, I go to bed early if I'm not doing anything, and if I DO go out I usually get to bed pretty late

BUT, I also have to work every other weekend, so sadly I still have to get to bed early most weekends