flusterer

The tortoise lays on its back, its belly baking in the hot sun, beating its legs trying to turn itself over, but it can't. Not without your help. But you're not helping.

Besides captcha and the Voight-Kampff, what other methods do you plan for preventing scammers and spammers of polluting the new dark mail system?

Are you familiar with Mailpile? How easy would it be for this privacy-aware email crowsourced project (or any other) to support the dark mail protocol?

I was thinking that maybe before a message it is sent for the first time from an unknown sender, then the receiving server may ask from the issuing server that the user solves a puzzle and attaches the answer to the message. If the same user is sending too many incorrect answers, that would be a good reason to flag as spam.

Another thing are encrypted mailing lists, or automated delivery of messages, I guess for that one users should have a white list.

Anyhow, thanks for your answers and for putting some thought into this, because I assume it is going to be very relevant.