I stumbled across two things I didn’t know existed before.

The Anti-Spam SMTP Proxy (ASSP) is exactly what the name suggests. It sits in front of your existing mailserver and runs various anti-spam measures. Linux users already have MailScanner which seems to bring various technologies together, but there’s something neat about being able to ‘drop in’ an anti-spam tool. (Almost like a Barracuda, except free.)

I also noticed Claros inTouch, which for some reason, I’ve never heard of. Which is a shame because, from the looks of it, it’s the best-looking webmail client on the face of the planet. (Yes, even cooler than RoundCube.) I haven’t looked into it too much, but it seems that it’s free (they refer to “free as a bird,” typically “free as in speech,” but it doesn’t look like you have to buy it, either), and it also seems that, being AJAX, it does POP/IMAP in addition to ‘normal’ webmail, which might be interesting.

Of course, I haven’t actually worked with either of these, but thought they might be interesting options.