Do Not Email
It's a bit trickier probably: I wonder what % of spam is a result of lists of legitimate users being sold (with the users' badly-informed permission)? It would be interesting to see this process become more transparent (e.g. if you get a spam you can figure out who sold your name).
Apr'03 http://www.wired.com/news/business/0,1367,58655,00.html |article Jul'03 article explaining the difficulties of implementation and suggesting alternatives.
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