I've beena fan of the whiteboards for a long time now too, and PostIts. I love PostIts. Sometimes I've got PostIts and whiteboard scribbles slapped all over the damn place in giant mess. I love it for plotting out backlinking strategies, and site structures and whatnot. It's nice to have something physical to stare at and play with, as opposed to just another diagram on the screen.
As far as sleep, get some exercise in your day. Sitting at a computer all day isn't burning any energy, also, computers and electronics have a way of "over stimulating" the mind. Take an hour of cool down time before going to bed. Don't just sit on the computer until you feel like clunking out. Go read a book, tinker on something in yoru garage, have a relaxing soak in a hottub or bath, even lay down and watch a bit of tv. Something to relax the mind a bit instead of taking on the brain overload that is internet.
TL;DR - Burn off excess energy with daily exercise, don't put too much computer time in during the dwindling hours of the day.