My emails are sent straight to my iPhone 4 through pop3 and I'm sick of getting spam!

I've not found a suitable spam blocker for my web mail so I'm wondering if anyone has come up with a solution for iPhone?

A kind of iblacklist but for emails, either in a separate app or add on?

I've searched everywhere and I'm yet to find anything. I would have thought developers would have been on that already?

I can't be the only one being driven crazy by spam???