CEgals - Female posters. Rarely post anything interesting, but hey, they're girls. Lyke omg! Often followed around by white knights (users who love them) and black knights (users who hate them).
Gimmick users - Users who only post about _one_ thing. Sometimes their username will reflect that. They are known to go through great lengths to somehow fit that one thing into a completely unrelated conversation, but if they're feeling lazy, or just suck at what they do, they'll simply spam topic after topic of their own.
CE"vets" - Posters who also frequent CEchat on AIM. Generally act condescending, but in reality they somehow find joy in being considered annoying as hell by the general populace. Go figure.
Experts - Make a topic about economics, politics, or religion, and these guys will swarm in, preaching from their soapboxes like they all have graduate degrees in said subjects. Ironically, most tend to be high school-aged.
Most other people on CE fit the profile of your typical internet forum user; white suburban kid between 14 and 19, loves bands like Sum 41 and Rise Against, nerdy, and a little bitter.