GOgroove SMARTmini BT ADVANCED Wireless In-Car Bluetooth FM Transmitter with Charging, Music Control and Hands-Free Calling for ANDROID, iPhone, Blackberry and Windows Smartphones
An added surprise is that when using this with the google maps app, the auditory directions automatically play over the music so that you can hear them!  This thing is easy to use and easy to set up with Bluetooth, though it doesn't always reconnect when I get into the car.  Also, when you press the button to search for available stations, it will often take you to stations that aren't completely clear, causing static (though, this happens in cities where there may not be any usable stations).  Overall, I'm