I was pondering this problem. I think that the real problem is spam, -not trolls. Trolls interact at least, and while they bait, I believe that some people actually enjoy being baited just for the love of argument and the chance to sound off. This is not a high or ideal form of discourse, but by the nature of their comments, trolls will not get upvoted in general, so their comments will reside lower on the totem pole. What I am more concerned about is people clogging up the UI with spammy links. Not a problem now, but could be in the future. I think that nixing a downvote button, and having a 'spam' button would suffice. If it's a spammy link, and enough people flag it as spam, then it can get demoted out of view. I think psychologically, naming the button as a spam flagger will reduce the number of people that will 'spite flag' on purpose, and the negation of a post due to being flagged for spam too many times could even be undone by some number of upvotes. It seems like you'd have to fiddle with it a little to get it right, but it seems like it could work in theory. Good posts get upvoted and grab the most mindshare. Trolls receive no (or few) upvotes and receive less mindshare (mitigated only by their trollin skillz), and spam gets flagged out of existence.