I like the idea to vote people off.
If you get enough “go away” votes- your gone.
Everyone could only have one vote per individual person. You could even change your vote if you change your mind.
Only you could see your current number and type of votes.
If a majority of the people think you suck- your gone.
If you keep the number of votes it takes to make someone “go away” high enough, you would only eliminate the super trolls.
Sure, another super troll would take his/her place, but it could make the “occasional troll” in all of us think twice before posting.