The person (typically male) who has accumulated a music library on their iPod that all others would dream of, but wastes it by insisting that one must only listen to their crappy On-The-Go playlists, or listen to it exclusively on shuffle without skipping songs; thus creating the Dentist Music Effect and therefore becoming the guy nobody likes.
Shane: "Have you seen Todd's iPod!?"
Shane: "Oh, well it has every song anyone could possibly ever want, AND he updates it regularly. Too bad he's a juke box zero and never lets me listen to anything but his Simon & Garfunkle playlist and his extensive collection of Louisiana Blue Grass.
Lisa: "What a fucker! I hate Todd!"