I can relate. I normally don't get more than 2-4 hours of sleep a night. Some nights I don't get any. The most I've gone without sleep was about 3-4 days.
I notice that if I tire myself out (exercise, walking, etc) all day, then I will be able to sleep at least 4 hours. I also have found that if I sleep in different places (bathroom floor, bedroom floor, etc) and positions, it helps sometimes too.