External FM Modulator is a $30 device that acts like a mini Radio station. It's a little transmitter smaller in size than a pack of cigarettes. It has a cord attached to it that plugs into your radio. Instead of plugging a set of headphones into a headphone jack of your music player(CD player, MP3, AM radio,etc.), you replace the headphones with this FM modulator. Setting an FM radio at the proper frequency will let you receive it over the airwaves, just like listening to a regular radio station. Alot of health clubs have this to broadcast music or TV to the people working out, so they receive broadcasts into their FM radio's while they excercise. I think Radio Shack has one, I just got mine from CompUSA. It has 4 frequencies to choose from.
Kevin