The only 'stamp' idea I like is having the originating system pay a computational 'duty'- this is to say it has to spend a few seconds of processor time computing some fragment of an algo (Grid COmputing model like SETI @HOME). For anyone wanting to send up to a thousand emails a day, this DUTY is meaningless (legitamate businesses and legit individual needs will rarely exceed a thousand or so). For a SpamNEt trying to sind millions a day- thats some serious cyclage!

However, the whoe idea is naive, unenforceable, and it begs the HUGE question of who pays who and who gets the processor time.

The best Idea out there in the public domain is to demand a Public Signature, like a THAWT CERT, be appended to every email. The Signature would have to be registered to an individual, and the checking of the key esxro could be tabulated: any more than a few thousand validations a day could be reported to the FCC for enforcement under new (as yet non-existant) anti-spam laws. The law would alos levy a fine to any SMTP/POP server passing along a non-signed and non validated email message.

But notice: there goes the anonymous utopia of the web as an intellectual commons- while it is the only method that would work for sure, it destroys the very foundations that makes the WWW sucha force for freedom and democracy (do you think the Iranian thaw, for example, could have happened without the WWW? I don't)

Frankly: filters are doomed. I know someone who proved the computational intractability of Spam Filters (one of my old fellow grad students) by relating it to a class of problems that are so complex as to require countably infinate time to compute- I have not seen the proof, but I have seen the 'walk-through' and it was pretty convincing.

I can think of a few things that might be able to solve this problem without destroying the anonymous web... Aint gonna say anything in a public forum until I convince myself that the ideas don't have merit or are not worth a lot of money.

Davin L.