My school does not supply a school email address. I also remember an article posted here a couple months ago that described Boston College not going to supply students with email addresses any longer. Their reason cited is that students have an online identity prior to college. Perhaps more and more schools will follow the same path.

My point is that requiring a .edu address is artificially restricting your potential, and most certainly legitimate, users.

I read RateMyProfessors and the information given is less detailed than the information I get talking to people in the halls of my school. The site definitely has a use, but a professor rating himself artificially high will probably contradict the actual widely held student view that the reader already knows.