SLUG Mailing List ArchivesQuoting Mary Gardiner <mary@xxxxxxxxxxxx>:
Everyone's solutions have been pretty interesting[1]. I'm surprised (although, yes, I knew) that there aren't less sysadmin-y solutions: blocking outgoing SMTP is getting pretty common. I feel bad users who just want to send their mail already and not carry around a SMTP setup cheatsheet for Outlook/Evo/something.
If you want to do something simple you could run a https Webmail server such as The Horde and then do all your email away from home through your web browser.
Steve Grady