Violent J

Insane Clown Posse's giving Michiganders short on masks a reason to bust open some Faygo and celebrate ... a helpful donation from the Juggalo world. Detroit's very own horrorcore hip-hop duo delivered more than 300 band shirts Wednesday to be made into masks, which will be distributed to…

Violent J -- one half of the rap group Insane Clown Posse -- says he left his car unattended for a grand total of ten minutes yesterday ... and when he came back, his car stereo was GONE. Sources close to Violent J -- real name Joseph Bruce -- tell us, the rapper and his pal were making a quick…