Few bands in the history of pop punk have proven as fun, cheeky and downright ambitious as Fall Out Boy. It's just about impossible to file them under a single genre. Funky R&B grooves, synth-pop bop, high-profile collabs with pop superstars and Queen-size glam rock jams: Everything is in play for these lovably scruffy boys. Much of their incision comes, of course, via Pete Wentz. As sarcastic as he is passionate, the singer mashes up punk barks, arena-sized howls and rap swagger with an agility that's as sharp as a switchblade.