Running a Community Mailing List Server?

WaldoJ asks: "I recently acquired an old Dell P133. So I fixed it up, and now it's got 32MB of RAM and 1.6GB of storage, running Linux and, as of these evening, it's running Sendmail, Apache and Mailman. I've got it plugged in with the rest of my servers, and I intend for this little system to serve as a free mailing list server for local organizations. Technically-speaking, everything is covered. But I can't help but wonder what sort of practical problems that I'll run into, like teaching folks how to administer a list on Mailman, understand what good a mailing list is, obeying mailing list etiquette, etc. Has anybody set up a community mail server like this? I'd like to avoid running into known, documented problems. OTOH, if this hasn't been done, I want to make sure to keep careful notes so that others can set up something similar with a minimum of hassle."