Communication: Type 0 Remailers

At first, there were the "type 0" remailers.

The alt.sex.* ones, and anon.penet.fi are the most well-known
You send a message to a server, who strips the headers and forwards the body.
You also get a pseudonym like an123865@anon.penet.fi that people can use to respond to you.
But the remailer operator has a master list matching the nyms to the real addresses!

This list is attackable, by legal (or extra-legal) means, and Julf Helsingus shut his remailer down rather than expose his users to risk.