I love my SME 7.2 server.
It is my home server for mail (fetchmail for external accounts), print, fileshare and VPN (OpenVPN). It sits behind my wireless linksys router. My wireless machines connect to it via vpn. It servers 7 users. It runs on a Duron 1.7 gig, 512 Megs, 80 gig Raid 1 mirror. It just runs 24x7.
I know a lot of you run it at home, at work and at your clients locations. I think a lot of us would love to hear about each others' successul installs. What contribs are you using? How much fun are you having just knowing that this kicks SBS butt?