I’ve been arguing online quite a lot today, perhaps most prominently on Dave Farber’s Interesting People list. I think the EFF are overstating the free speech implications of authenticated email, and that their arguments against new technologies are wrong.
http://www.interesting-people.org/archives/interesting-people/200502/msg00247.html
This post happened to coincide with a discussion on the IETF email message format discussion list about syntax changes to support anonymous messages, e.g. by omitting the From: field.
http://www.imc.org/ietf-822/mail-archive/maillist.html
I think this is all pretty worthless. If you are serious about anonymity you should use serious anonymizing technology like mixmaster. The illusory secrecy provided by hiding your email address (but not your IP address) will just get you in trouble.