First problem: anonymity + some assholes = mess (the Penny Arcade version:[1])<p>Facebook dealt with this by requiring &quot;real names&quot;.  Except from some whining from drag queens, this has worked well.<p>Wikipedia has an ongoing struggle with this, but because everything on Wikipedia can be undone, users have reputations, and the asshole fraction isn&#x27;t that large, Wikipedia continues to work.<p>Any system where fake identities can be created in bulk at low cost suffers badly from this problem.  Email, especially.  Interestingly, if you have conversations, and not much happens based on single messages, it&#x27;s less of a problem.  Twitter and IRC are examples.<p>Second problem: once the bulk junk identity problem is under control, how do you get people to behave reasonably well?  Wikipedia does this surprisingly well, with a complex set of rules and an explicit requirement of civility.  (Many new editors complain that it&#x27;s hard to edit Wikipedia, but that&#x27;s because they treat it like a blog.  Think of it more like checking out something from Github and submitting a pull request.)<p>Newspaper comment sections do this badly.  Karma-based systems such as the one here and on Slashdot do it reasonably well.  Fancier karma systems are possible; Civil Comments seems to be using something like the ELO algorithm.  It takes a lot of user time to crowdsource such rankings, and that&#x27;s a scarce resource.  Not many people want to do Mechanical Turk work for free.<p>[1] <a href="https:&#x2F;&#x2F;www.penny-arcade.com&#x2F;comic&#x2F;2004&#x2F;03&#x2F;19" rel="nofollow">https:&#x2F;&#x2F;www.penny-arcade.com&#x2F;comic&#x2F;2004&#x2F;03&#x2F;19</a>