Penet Remailer

The Penet remailer (anon.penet.fi) was a pseudonymous remailer (type 0) operated by Johan "Julf" Helsingius of Finland from 1993 to 1996. Its initial creation stemmed from an argument in a Finnish newsgroup over whether people should be required to tie their real name to their online communications. Julf believed that people should not—indeed, could not—be required to do so. In his own words:

"Some people from a university network really argued about if everybody should put their proper name on the messages and everybody should be accountable, so you could actually verify that it is the person who is sending the messages. And I kept arguing that the Internet just doesn't work that way, and if somebody actually tries to enforce that, the Internet will always find a solution around it. And just to prove my point, I spent two days or something cooking up the first version of the server, just to prove a point."

Read more about Penet Remailer:  Implementation, First Compromise, Second Compromise, Other Attacks, Third Compromise and Shutdown