I must be a genetic short sleeper: 4 hours and I'm awake, as in my eyes won't stay shut. 5 hours and I'm groggy. Been this way for quite a while, and I used to stress about it, but now I just get up and get things done. I do take a nap here and there, but maybe once a month? However, I am somewhat of a health nut, crunches and core stuff during compiles, and a hard cardio mid afternoon. All this while coding 10 to 14 hours a day. Working from home, no commute, and a boss 12 time zones away, I've been able to get pretty extreme because I really like my work.