| On the mail side I believe there is a POP3 extension which allows sending
| mail. Since POP requires a password that might meet your needs. However I
| suspect you'll have trouble convincing browser authors to support a feature
| that has a rather restricted domain like that.
I was thinking more in terms of the browser inserting a magic cookie
in outgoing (SMTP and/or NNTP) messages, rather than using a
different protocol to send the messages
e.g.
X-Sender: nazgul@utopia.com (verified)
X-Mailer: ACME WebGobbler
So the aim is really to discourage the casual user from mucking
about, since their real identity will be stamped on the messages they
send
And the code to implement this using the authentication elements of
(say) POP, IMAP or FTP would be quite, quite, trivial
Martin