You really ought to try out OddPost (
www.oddpost.com) because they have what is probably the slickest web based email client around.
Really, it's amazing--you won't believe the features they've been able to put in there. Not only is the client great, but they have bayesian filtering for getting rid of spam, and built in blog/news aggregation. Give it a try, there's a 30 day free trial so you can see if it's worth the $30/yr.