Not that all of these things apply specifically to college life - most can be applied to "normal" life so may be worth reading.
If you've something to contribute, please post a reply and I'll add it to the list. This is more of a work in progress as I find new ways to save money at odd intervals.
Step 1: Transportation
Not like you won't being doing enough of this between classes, but walking to other places is a great way to save money. Gas is hovering around $3.80 a gallon as I write this whereas walking only costs as much as the food you run on. If you live in a city where everything is fairly close together, you can most likely get away with walking for 95% of your travel.
Most (if not all) forms of mass transit within cities (buses, subways, etc.) give student discounts. If you use mass transit frequently enough, buy a monthly pass. There might even be a bus or train that runs between your school and your hometown. I can take the Coach bus home from college for $1.25 one way (about a 40 mile drive).
You can also buy a bicycle (or salvage one, if you're savvy enough). Costs for that are only maintenance-related and I don't know a university that doesn't have a bike rack outside every campus building.
If you have to use a motorized vehicle, try to limit it to something small like a moped or a motorcycle. Not only do they get great mileage but most colleges offer discounted (or free!) parking for such vehicles. If you have to use a car, try to carpool. And, if possible, drive a car that gets good mileage (I know, if you're as broke as me you probably can't afford one!)