This guy is amazing. Richie Branson raps about anime. Here is his channel: http://www.youtube.com/user/RichieBranson?feature=watch

Toonami even used one of his songs in a short promo: http://www.youtube.com/watch?v=eNEsz347UBU&feature=channel&list=UL

Seriously check this guy out. He's awesome.