A few years ago, I bought an FM transmitter that ran on batteries and plugs into the headphone port of an mp3 player to play through the car stereo, It had been rattling around in a drawer for a few years, Until I came up with this.
It still rattles around in the drawer, but I get more use out of it. Repurposed in the opposite direction by transmitting from my PC and or TV to an mp3 player with an FM tuner.
I can wander about and still hear my music or movies without disturbing others.
Great for late nights in the laboratory!