Plug the 45,000 Station Car Radio from Hammacher Schlemmer into your car’s 12V power outlet, connect it to your iPhone via Bluetooth, and you can stream any of 45,000 AM/FM and internet radio stations to an open FM station on your car’s radio. A free iPhone app streams the stations, including nationwide NPR stations as well as Pandora and Grooveshark stations. The buttons on the transmitter can control the iPhone’s app for scanning for stations. And if your car’s radio has an auxiliary input, you can connect the transmitter directly so you don’t have to worry about radio interference. The transmitter is $99.99, but I’m thinking the real expense will come from data plan overages.