The social impact from customer to customer is usually a beautiful thing, but well, not all human beings behave beautifully.
In any social network there are going to be those who--how do I put this delicately--are assholes, as immortalized in this classic Penny Arcade gem. There is little doubt that these people are out there and that they cause harm. If you’ve ever made the mistake of connecting to XBox Live voice chat with random teammates in a shooter title, I’m sure you know what I’m talking about. It’s some 12 year old kid (or someone behaving like one) screaming obscenities, telling you you suck, etc., etc.
The Internet parlance for this sort of person is of course “troll.” Some of these players are awful and don’t realize it, while others take direct glee from the way they harm and annoy others. What does science have to say about this? Like just about anything, it can be measured, and in this case the process also suggests a solution.