Building on the rapping style of eccentrics Kool Keith and Del tha Funkee Homosapien, Def Jux headliner Aesop Rock became one of the hottest MCs in the post-millennial underground. After a pair of self-released LPs (Appleseed, Music for Earthworms), he recorded Float for Mush in 2000. The former Ian Bavitz then issued a pair of singles -- "Coma" and "Boom Box" -- for another underground rap label paragon, Definitive Jux. His second full-length, 200...