Version 0.1.N
python2.3, twisted, gnupg
http://petmail.lothar.com/  [apt-get source available]
simplistic address and ticket server running that you can play with
What's implemented:
 message send, receive, permission checking, ticket checking
 return permission, introductions
What's not:
 remailer support [code is about 30% done]
 NNTP support (alt.anonymous.messages)
What is in prototype form:
 address server protocol
 ticket server is limited to image->text -type CAPTCHA, protocol needs thought

[demo]
show modifying ID Record
show address book, adding records (searching, pasting armored form)
["for the demo, everything is running locally on my laptop, and we're using
a direct TCP connection for the Transport"]
show Bob sending message to Alice, requiring CAPTCHA ticket
show Alice receiving the message
show Bob's auto-granted return permission
show Alice adding Bob to the address book, show Bob getting specific permission
show Bob sending message to alice, not requiring ticket

[balsa proxy]

[maybe: introduction]

radix:
enumerated problems
why other solutions don't work
why petmail would