I'd recommend Mail Washer. It acts as a "bridge" between your e-mail server (where your e-mail is stored on your ISP's computer) and your e-mail program.

It shows you what e-mails are waiting for you to download, and, what of those e-mails contain attachments. You can then make an executive decision as to what you want to allow to come into your computer (using your e-mail program to download the mail from your server) or, you can delete whatever e-mails you want at the server level, without those seeing the light of day on your computer. I like it alot.