Saw this at halfords online after i bought Belkin Tunebase for £40. It's only for those people who are stuck with a non-upgradeable car cd player. I've not tried this but the Belkin Tunebase is really good, i can answer calls with handsfree and switch on satnav on my iphone.
RoadTrip makes enjoying an iPod or iPod mini in the car convenient and easy. The RoadTrip plugs into any auto power outlet or lighter adapter and provides an adjustable cradle to charge and hold any docking iPod including the new 4G iPods and the iPod mini.
The RoadTrip transmitter can then be set to broadcast iPod's music to any FM frequency from 88.1 to 107.9. Its backlit screen shows which frequency RoadTrip is currently broadcasting -and can easily be adjusted via buttons located directly on the front of the unit.
Your iPod's audio is transmitted through the connected dock on the bottom of iPod.
The RoadTrip is a great FM transmitter and car charger for the iPod in the car, but what makes RoadTrip truly unique is its removable transmitter module that can also broadcast music from a Mac or PC. The package includes a combination USB power and audio connector cable that attaches any USB equipped computer to the module. Users can then play their iTunes music, movie audio or presentation sound to any FM stereo close by.
The RoadTrip is compatible with all docking iPods, including the iPod nano and the new iPod with video. iPods with FireWire ports on top (1st and 2nd gen) will not work with the RoadTrip.