I remember when the hoopla was about radio scanners eavesdropping on analog cordless phones. Every new technology seems to introduce a new way to violate our privacy. This little gem seems to allow capturing or recording audio while a bluetooth device is not actually in a call. This would mean that you can eavesdrop from room-to-room or with a laptop, from car-to-car at a stoplight even when someone is not using their bluetooth headset.
Here is a link to a useful collection of bluetooth hacking tools.
http://www.security-hacks.com/2007/05/25/essential-bluetooth-hacking-tools
Here is a link to a video demonstrating the bluetooth hack.
http://www.hackszine.com/blog/archive/2007/12/eavesdropping_on_bluetooth_hea.html
