Such a Cool little device! Plug this thingy into any computer with USB and it appears as a new sound card. Then tell one of your Music programs to play to the new sound card and this little device starts transmitting the Music on FM Radio :)! Supports 107.3MHz, 107.5MHz, 107.7MHz & 107.9MHz and will work in windows, linux or MacOS.
You could easily get this to work with winamp or the equiv, and if you selected it as your default sound card, it would allow any sounds your computer made to come through your Stereo which is nice for those who have Cheap stereo's that don't have AUX.
You could be listening to the Music on a stereo while outside and the stereo would let you know when some one signed on or started chatting to you on your computer!
More importantly though a private short range radio station with what ever music you want no adverts, and unlike the Stereo you wouldn't need to keep on changing CD's.