text_combined: gordon mohr gojomousanet ideal mailwall allow message passthrough many ways sender membership personal whitelist one many external whitelists respect payment small fee via website paypal link demonstration special permessage effort either via computational challenge hashcash challenge requires humanlevel flexibility followthrough sender manual whitelisting inclusion legallyenforceable guarantee mail unsolicited commercial pitch one example class guarantee would posted bond convincing analysis software agent mine want see mail based content distribution list theres need one might overlap manual process passing message might require assertion legallyenforceable guarantee messages contents passing certain tests might add address persistent whitelist slightly determined legitimate correspondent would able find multiple ways get mail read spammers would face situation marginal cost reaching much much greater expected return economically irrational spammers religiouspolitical zealots would get traffic background trickle rather annoying torrent gordon httpxentcommailmanlistinfofork fri 9 aug 2002 151847 0700 david friedman mail money