A couple of talentless retards who 'rap' about unnecessarily violent and disturbing things. Personally, I think they should be shut down because they fucking suck ass and probably have the IQ of a homeless mentally ill crackhead black man. Their followers, 'juggalos and juggalettes', are incredibly annoying because all they do is run their giant retard mouths about how they'll fuck anyone up who messes with their 'family.' They are typically overweight suburbanites who pretend to be tough and hardcore.
Actual sample of Insane Clown Posse lyrics:
"yeah, maybe I can stand a little Conway Twitty while I'm sucking on redneck titty."
-the lyrical masterpeice, "Redneck Hoe"