Just because you don't see the Spam in your mailbox because you've set up your Spam filters well doesn't mean you aren't a victim of some of the underlying issues. The millions and millions of Spam messages sent out every day to try and get that .01% return rate are still choking up processing power on DNS servers and taking up bandwidth.

I've dealt with wedohosting.com for several years now, they do e-mail only hosting. They are a Canadian company and therefore not bound by US law when it comes to losing your privacy. Decent price points in Canadian funds as well.