There are plenty of artists working in hip hop who are really into cartoons and comic books, but I don't think they take it far enough. You know who does? MF Doom, the metal mask-wearing emcee who has based his entire persona on Fantastic Four villain Dr. Doom. Exhibit A: "Hey," a song from his debut solo LP Operation:Doomsday, a track built entirely on Scooby-Doo samples.
MF Doom - Hey! [youtube]