Mike Stall comments on how not to organize your mail. I recently read David Allen's Getting Things Done, after reading a recommendation for Take Back Your Life by Sally McGhee, visiting the Amazon site, and reading a review that said it was almost the same as GTD. I decided at that point to take the reviewer's advice and go to the original. It was definitely a good read, and I subscribed to the blog. The main thing I took away from the book about email organization was to keep your Inbox empty. The auther recommends creating three folders: Actions, To Read, and Reference. As you go through your Inbox, determine whether you can take care of the message in two minutes; if so, do it. Otherwise, move the message to the To Read folder if it is something you need to look at when you have time; move the message to the Reference folder if it's something you might need to check back with someday; and otherwise move it to the Actions folder.
This is a huge oversimplification of course, and the book recommends a few other tricks. I am deficient in that I don't carry a personal organizer of any kind, for example. But I'm slowly working towards full organization!