John
I can thoroughly recommend Mailwasher. The basic version is free.
You set your email client (Outlook Express, Incredimail etc) not to collect email automatically (so you have to click on Receive). Mailwasher collects the Headers only from your ISP. It has a set of rules; for example, If To Is Not Steve Maskery Then Mark for Deletion. It doesn't stop people sending them, but at least you can identify them and delete them before you download them to your own computer and have to see the offensive images.
The rules are easy. I have my own domain name (stevemaskery.co.uk) but it is not hosted, any email to this domain just gets redirected to my ISP proper (if NTL can be called a proper ISP these days). Almost ALL my junk mail gets sent directly to my ntl account, so it is easy to differentiate stuff that has come to there rather than via my legit email address.
Anyway, give it a try.
Cheers
Steve
(who, if he had accepted every offer of an extra 3", would now be walking with a very pronounced limp)
(and anyway, why don't these people offer something useful, like making that board grow an extra 3" so I can have another go at cutting it right?)