If you're looking for a bundle of tools to do it all, take a look at
Untangle. A popular VMware appliance, Untangle protects against viruses, spyware, phishing, spam, and other threats and nuisances, bundling the likes of ClamAV, Snort, SpamAssassin, OpenVPN, iptables, and other open source goodies with its own scanning engine. Untangle combines everything into a single server, and includes updates to the applications, various signatures, filters, and category lists along with nice reporting.
FULL REPORT ...