I second the suggestions for using GTD. It really saved me from dealing with school emails the previous year. Now spam isn't allowed, but before students at my university used the email system for basically everything; like finding rides, announcing club events, and selling things. I have over 4800 emails sitting in my trash can going back from September 2007.

And one-touch handling really helped me deal with the flood of emails. After I started doing it regularly, I was usually able to clear out my inbox whenever I logged in. But it also helped that most of it was junk and I could immediately trash.