The Oddities were a faction that existed during '98-'99. It featured the likes of Kurrgan, Golga (formerly Earthquake) and Luna Vachon. The Oddities were no technical marvels in the ring, yet they quickly rose to popularity with the WWF audience. This was because if their message of "hey, who cares if your a freak, come party it up with us".
A BIG part of the gimmicks success was their entrance. They would come out dancing, jumping around and generally whipping the crowd into a frenzy. The theme that accompanied this was an altered version of an Insane Clown Posse track (original here). They changed the lyrics to reflect the Oddities characters, and would often accompany them to the ring while singing it live.
Now say what you want about the ICP, but this theme was fantastic. It was catchy as hell, simple enough for the crowd to sing along too and had the perfect beat for people to wave their arms in the air and be a part of the show. The effect it had was incredible and definitely helped make the Oddities. It was a truly excellent theme.