I've now got pop3s and smtps working on my server. Today I added https for webmail access. All three are done with stunnel.
I set up ClamAV with TrashScan. I then set up a folder for viruses to go into so users could download them with webmail (I didn't really want to send other people's mail to /dev/null). Now that I was on a roll all was left to do was install mbox-purge so I could write a little shell script to only keep a month's worth of viruses about.
Of course, I'm using this as an excuse to delay doing laundry, dishes, and tidying the house :)