Much like putting a DVR into a VHS player, Belkin's TuneCast Auto Live utilizes really good technology to support something that isn't all that great. More specifically, it uses GPS coordinates and the iPhone (3.0) to identify the best FM frequencies.
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Combining the TuneCast Auto Live transmitter and the ClearScan app for the iPhone users with OS 3.0 can tap into the GPS functionality to locate the best radio frequency to play music in the car (along with the recommendations of other users). In addition, both iPhone and iPod Touch users can use their devices to manually change frequencies and set favorite channels as presets. The device will be available in the early fall for $80, but I'm waiting for streaming Bluetooth. [Belkin]