Merlin over at 43folders wrote a great article about cleaning up email. link. Most of the other sites on the blogroll have something as well. As for my school email, I simply use three folders: Next Actions (things I need to do or respond to), Reference (links or emails I may need to refer to--as few as possible), and Waiting For (usually copies of email requests I've made and am waiting on a response from).
The other best thing you can do is forward reference stuff, fun forwarded emails from friends or colleagues, or anything else you'd like to keep into a big searchable email account like gmail (Google's email) or Yahoo mail. That way you're not tying up precious school server space and you're keeping your work email light and clean (like a ninja!) so you don't have it clogging up and causing stress.
Also, if you get a forwarded email you'd like to pass on, forward it to your personal email, then forward it on from there (and mostly to other friends' personal emails). Then you won't see rants like the one earlier and everyone at work will be happier.
