In my off-line newsreader, Eudora, (which ironically is also the subject of the message attached below--must be a plot), it's easy enough to mark all the stuff from some anonymous site for deletion.
This is only possible if there are few, well known, anonymous sites, and/or if all anonymous aliases look similar, such as an1234. How do you know if KSDF32@KMUVAX is an anonymous address, or a real user login? I also expect to see pseudonyms that look like real names. I don't think it would be too hard to pick a random first and last name from a list of real names, and create a From: line like jsmith@someplace.edu (John Smith) which will look just like a regular address. Even the remailers that don't create reply-able aliases could generate random real-looking From: lines, just to make the posts look non-anonymous. The only possible solution would be to ignore all messages not from addresses you trust. This is basically the "don't talk to strangers" policy. -- Yanek Martinson yanek@novavax.nova.edu