The classic one is sex. There are many "middle class" folks with proclivities outside of the socially dominant envelope of wherever they are. If those proclivit

The classic one is sex. There are many "middle class" folks with proclivities outside of the socially dominant envelope of wherever they are. If those proclivities became publicly known, they would have negative repercussions ranging from social stigma through death. This is highly context dependent, of course - swinger-couples in one church towns may end up wanting to move; a gay man in many places may end up not being able to. Both have strong interests in securely discussing things without attaching their names to the communications. The first large experiment with anonymous remailers was anon.penet.fi[1], and I think it demonstrated how much demand for anonymous communication there is - it had over half a million users in the mid-90s, when a vastly smaller percentage of the population was online. [1] Not strongly anonymous, and people suffered because of that. The Mixmaster remailer network was significantly stronger, but was harder and less forgiving to use, distributed and frequently changing, and somewhat politicized.