Ok I have the exact same thing going on, i swear my dorm has a poltergeist. My roomate and I refer to my ipaq as "psycho ipaq" every night guaranteed, right after we get into bed, it will turn on and off atleast 3 times before we fall asleep. And it will turn itself on and off 10 more times by morning. Strange thing is it will do this same thing whether we go to bed at midnight or 4 am. Even if it has been cradled when i was on the computer before I go to bed. My printer also goes on and off to its own pleasure. I can no longer stand those annoying sounds XP plays when it finds new hardware.
Oh and just so you all know that this is a poltergeist and not just electronic failure; Every night I keep a powerade bottle filled with water right next to my bed on a shelf on my wall. Well if it ever got knocked down, it would poor water all over me. Well one night I was lying in bed asleep, and I suddenly shot awake and saw my powerade bottle float right over my bed and dropped right next to my bed and spilled the water on the floor. I looked at my roomate who also suddenly shot awake and looked at me for no appearant reason. I didn't know what happened, and I discussed it with my roomate in the morning. We thought maybe I hit it somehow without knowing. Well there is no way because it just floated right over me and completely missed falling on me and fell on the floor, which would be impossible just by hitting it accidently.
I kid you not, true stories of my haunted dorm. It's all good though cause we figure it's a cool and chill poltergeist. If it was dick it would have dropped the water on me and F up my ipaq, but it's chill and just wants some attention.