The hashcash tool allows you to create hashcash stamps to attach to
emails you send, and to verify hashcash stamps attached to emails you
receive. Email senders attach hashcash stamps with the X-Hashcash:
header. A hashcash stamp constitutes a proof-of-work which takes a
parameterizable amount of work to compute for the sender. The
recipient can verify received stamps efficiently.
From: Armin Wolfermann <aw@osn.de>
ok alek@
