This Harman Kardon iPod controller is one of the best in-car iPod solutions ever made. Seriously, the product has been out for a few years, but it works great. Installation isn’t a breeze, though cause it should be wired directly into the car stereo, but the interface and sound quality is solid. Amazon has the docking edition on sale for only $39.99 too. Trust me, it’s a hell of deal for the $179 device.
You may need to have a pro – or at least someone who thinks he is a professional – install the device. The HK device has three main parts that must be wired together [pdf link]. The controller nob needs to be placed within arms reach, the screen installed in a convenient out-of-the-way location, and the iPod controller hooked up to 12v power and interfaced with the car’s stereo. Once installed though, it works like a high-quality HK product should.