But the original question was not about privacy and encryption. If you are going to discuss an issue which for some reason requires a good measure of confidentiality on a mailing list, the issue is not keeping the discussion within the list confidential but preventing normal users from finding out who is posting what, who is on the list, and so on. I don't see how encrypting the text could help, and the PEM business doesn't encrypt the headers. It all depends on the degree of security you need. Listening to Internet lines is pretty easy, so if you're worried about people with that kind of approach you just can't use the Internet to discuss such issues, because it isn't a safe network. Again, encryption will not help as it isn't the text which is confidential, but the name of the person who sent it. While mail headers can be forged easily (this time with a good reason), it would still be possible for someone with enough determination to trace the forgery to the host that did it, unless it were done really very professionally (and we wouldn't want such high-quality forging tools available to the masses with a nice click-and-forge interface, would we?). If you can trust people, computers and lines at your site, you can arrange for the anonymous mapping to be performed there and hackers can listen all they want to the backbone lines. On the other hand, I'm pretty sure that if you fill up one of these anonymous mailboxes you will sooner or later get a message back from a mail daemon saying "imail: unknown imail error -22987437" with the actual address in it ;-) If on the other hand your concern is that your name and address would show on the list, there are anonymous servers for that. Eric