I've got a similar thing going on-- if you're not already, read for an hour or so in bed. It keeps your mind from jumping around too much. Might I suggest "The Moon and Sixpence"? It's past copyright, so it's free, too.
I dunno, do a couple really intense math problems before bed. Whatever'll get your mind in line for a bit, but reading is probably easier/better than that. Get a dog or something and cuddle it! They're adorable and sleep-inducing.