Non-members: to contact members, e-mail firstname.lastname@example.org
In general, I don't think it's a good idea for Mudcatters to post personal e-mail addresses (their own, of that of others) in the Forum. Occasionally, a non-member will want to make contact with a member, and Mudcatters will often instruct the Guest to join Mudcat so they can send a personal message. I have an easier solution - have them e-mail their message to Mudcat's Registrar, email@example.com, and he will be glad to forward the e-mail to the member.
Don't bother trying to protect me by posting my email in any sort of code like "joe(at)mudcat(dot)org" - my e-mail is intended to be public, and I just put up with the Spam. Thank you for your concern, but it isn't necessary. Feel free to post firstname.lastname@example.org wherever you like.
I have no way of contacting Guests unless they have furnished an email address to me or the Forum for some reason. And we never release member registration information to anyone.