I'm having several cases where people who received the password claimed that they didn't sign up. For this case, also to prevent misuse of the signup feature, e.g. someone could try to bother someone by signing them up repeatedly so they get the signup info, a feature would be great where they can reply with "cancel" in the subject and this would delete their acount and place their e-mail address in the badmail list. I've been having to do this manually, and it would be great to have this automatically done. Any ideas or suggestions? I'd love to see this at least as a hack, but I think it also would make a great (optional) addition to the official release version.