Your car should be packed with: Clothes, bedding, laptop/computer, backpack, some paper to write on, pens, and a large TV. I helped freshmen move in one year at my University and I can tell you that 80% of the things they bring are unnecessary. If you can't think of an regular use for something don't bring it.
One of those small pillows for lecture courses, your phone, ipod and or w.e music listening device with headphones. Sunglasses which you can wear in class so you can sleep while sitting up straight if you forget your pillow.