I am using this one now for several years and there is no way i would open my email program anymore without first weeding all junk on the isp or my domain server,that way can't ever get infected by anything thorugh emails.
Mailwasher pro..there is also free version you can use i believe but with limited number of email addresses.
The paid version is one time fee for ever and imo real worth the peace of mind.
You can mark friends,blacklist,bounce specific emails or by domains and all it takes is one time action and you are all set.
Works with any pop3 and imap as well.
If you use outlook then its great,if you use web mails no need in that.
I like using outlook where in one click all my incoming emails downloaded at once using that and i can browse them and mark for action on the isp server prior to downloading anything to my hard drive.
http://www.firetrust.com/products/mailwasher-pro