you might want to have a look at popfile. http://popfile.sourceforge.net/

The way it works is, it runs on your machine and checks all your inboxes (this makes it great for families or people with multiple accounts). Then it filters the email for you. Whatever email client you use, you set it to download email from the popfile server running on a port on your own machine.

I hear it's pretty good once you train it.