Radio Frequency apps?

[sconnary32]

"Mobile phones and telephone towers emit microwave radiation, which is in the radio frequency radiation (RFR) part of the spectrum of electromagnetic waves."

If the above is true would it be possible to create an app that would allow my G1 to play on my car radio? I know you can buy a device to do it but if i could keep my phone charging and listen on my car that would be great. Not to mention using it in the house or anywhere with a radio tuner.

Thanks,
Scott