8. RBX
A lot of confused people with emotions already close to the surface open up on Yahoo! answers hoping that some kind hearted internet surfer will give them the answers to life's questions. In other words, perfect troll fodder asking for it. Naturally, what happens is, they bump into RBX, who gives them a politically incorrect, rude answer, which may actually work. Here is an example:
7. The Team Roomba Griefers
Trolls on online multiplayer games are called "griefers". Team Roomba is the most notorious clan when it comes to griefing. These are not the kind of griefers that have fun just causing meaningless trouble, or doing things against a strategy. Instead, they set up a room in a game in a certain way, and then turn it into something entirely different. For example, in this video (not safe for work, has loads of curses), the Team Roomba Griefers have set up a Team Fortress 2 room in such a way, that as soon as you enter, you have to answer a trivia question, and if you answer wrong, you are killed right away. They effectively transformed a massive online multiplayer first person shooter into a massive online multiplayer first person trivia quiz shooter, and the best thing was that players actually enjoyed it and were spawning into the room to be griefed!