In the last couple of weeks I have had occasion to observe two different small email lists, a neigborhood one and a sports team one, devolve into bitchfests of fairly epic proportions. It is not that surprising when people post rude or cruel comments anonymously on the internet, but I was surprised to see a comparable level of asshattery on small lists (a few dozen people each) of people who actually know each other and/or live very near each other.
People on both lists have suggested that the problem is email itself, and I think that is probably right. When people talk In Real Life, even if they are really pissed off, most of the time the human conflict-avoidance instinct, combined with the urge to not look like an dickhead, kicks in to keep everybody vaguely civil. But when it's just you and your computer screen, you don't see anybody's surprised or hurt or bemused expressions when you start to talk like a crazy person. So it's easy to work yourself into a later of self-righteous anger and to make dramatic pronouncements that you just would not make in person. Then the problem becomes self-perpetuating, because once somebody has tossed some rude or email thought out there, other people get annoyed that somebody is clogging their inbox with nonsense or has destroyed their beloved email list, and they start to pile on too.
Anyway, this is all fairly depressing, especially since I conduct such a large portion of my life on email. I'm not sure if there's anything to be done other than to throw out the occasional "I think everybody on this list is great and we would all get along fine if we were talking in person!" But that kind of only goes so far.