LinuxQuestions.org - POP3 Proxy for Spam/Virus Scanning

I have a small home network with both Windows and *nix boxes setup. Depending on what I am working on at the moment, I check my email accounts from different machines. I would like to setup some kind of proxy server that all of my machines can connect to and download mail that has been scanned for spam and viruses.

Here's a little more detail:

I have 7 PC's running behind a firewall (Smoothwall). I have many email accounts that I check, but the majority all come from the same domain (a website/domain name I own but do not maintain locally). Normally, I connect directly to the remote POP3 server from my MUA (Outlook, Eudora, etc.). I would like to have a separate machine (Linux, any distro is fine) download the mail from each account and scan it for viruses and spam. The MUA would then be able to grab the scanned mail from the proxy. My plan was to use Spamassassin to check for spam. I have not done too much research on the virus scanner yet. If anybody can point me in the right direction, I would really appreciate it. I'm not a Linux expert, but I feel pretty comfortable following documentation/how-to's.

Thanks for your help!