I wasn’t really sure how to categorize this entry so I hope you agree that being under "Computers and Internet" is the right place.
Anyway, I am an avid fan of Bluetooth Headsets for using my cell phone.  I am on my phone about 2,000 minutes each month and many times needs both hands free since I do tech support.
I also like music and have been looking for an inexpensive bluetooth stereo headset but before now that was hard to find.
Now, I have found the best of both worlds!  A Bluetooth Stereo Headset that is also a wireless phone headset!  It allows the user to be listening to MP3’s on their MP3 phone and then answer the phone if it rings and it automatically mutes the music! 
All this and under $50!  Here are some details….

MotoRokr S9 – Behind the head Bluetooth Stereo Headphone and Mobilephone device.

Ultra lightweight
When comfort is a priority, the MOTOROKRTM S9 won’t weigh you down. Weighing barely an ounce, the MOTOROKRTM S9 is lighter than most sunglasses! The behind-the-head form and small ear buds (1.3 centimeters) help provide true comfort – even during extended use

Ideal workout partner
Combining ease-of-use with the latest Bluetooth® wireless technology, the water and sweat resistant MOTOROKRTM S9 is the ideal wireless headwear for the active music lover. Now, be connected and listen to your favorite songs during those tough workouts, without getting tangled in wires!2

Integrated controls
Integrated touch sensitive controls found on the headphones enable you to easily manage volume, track controls and calls. Play your music or answer a call by simply pressing the buttons on either side of the headphones.

True mobile music
Enjoy the ultimate wireless music experience. Connect with a compatible Bluetooth® enabled music phone or Adapter for iPod®.1 MOTOROKRTM S9 offers version 2.0 Bluetooth wireless technology for better call quality, less interference and faster connections.