TuneIn

found this while i was a looking at through a sideshow of philips technology from business week:

Enabling music lovers to share tunes legally was the inspiration for TuneIn. The Next Simplicity project is still in prototype phase but could allow people carrying the small yet savvy gadget to broadcast their music to others in the street. Press one button to tune into what another TuneIn carrier is listening to. Press another to listen to your own music. The device is designed to encourage like-minded music fans to talk to each other in public spaces.