Rap is a relatively young genre, one that only really came into the mainstream in the late '70s with Sugarhill Gang's "Rapper's Delight." As it started to morph and mold and become this perpetual force of excitement in the mainstream, all sorts of artists took some inspiration for themselves, spreading some of that spoken-word butter on their otherwise traditional rock-informed toast. The result? A quick breakfast for some, and a satisfying meal for others. Here are some of the best and worst dabblers in the 30-something-year-old genre, who more often than not inevitably define themselves by how well they can look in from the outside.