JBL's SoundFly lineup is one of the rarer breeds of wireless speaker we've come across: it's much like an earlier AirPort Express made solely for audio, designed to be as unintrusive as possible while it kicks out the jams. Those who find that stealthy sound appealing will be glad to hear that the more advanced of the two SoundFly speakers, the SoundFly Air, is now shipping. The 20W box will play audio streamed from any