Thank you for this work!! I have been thinking a lot lately about the similarities with bitcoin and pgp. Both have public key cryptography, both have signatures, both are just systems of sending cryptographicallly signed messages. Big difference is bitcoin intersects with a blockchain to assure assurance at a global level and of course securitize a database/ledger of record of not double spending the transactions or messages. And boom one becomes money because of this genius collection of technologies.