Or, you could just do PGP/MIME + SMTP over Tor hidden services living on home computers, and not invent any new protocols at all. :-) This allows p2p delivery w

Or, you could just do PGP/MIME + SMTP over Tor hidden services living on home computers, and not invent any new protocols at all. :-) This allows p2p delivery with strong encryption and anonymity of the transmission, while the message content can still be encrypted and signed for verification that you are talking to the right person. This is currently Mailpile's vaguely planned "maximum privacy" mode, with the backwards compatible fallback being normal PGP/MIME over the normal Internet. Anonymity from the POV of the sender/recipient is not characteristic of this sytem, and it doesn't give perfect forward secrecy/deniability like OTR. But most people consider anonymous e-mail to be spam. If you need PFS, just use OTR, it works. (Note: we have yet to do formal threat modeling and this plan may change.)