Basicaly a really strong urge to hear a song you either haven't heard in a long time or used to hearing that song most of the time.
It can affect just about anyone regardless of what genre they like
Person A - It is hard to believe I haven't heard much of metallica lately
Person B - I know dude they are the best on the whole damn planet most their stuff really gives me a song craving
*Plugs in ipod selects the song metalica master of puppets offers Person B ear piece*
Person A - hear will this feed your song craving