DLO's Transdock Direct ($59) is an in-car charging accessory for the Apple iPod or iPhone that includes a line-output jack and a secondary power output. Make no mistake, however, the DLO Transdock Direct is not an FM transmitter. To get audio from the Transdock Direct, you'll need a car stereo with a line-input jack or a cassette adapter.
The Transdock Direct is essentially a glorified in-car iPod charger, since your iPod already offers a 3.5mm audio output, and the additional 12-volt power socket only serves to replace the outlet taken by the product. If power is all you seek, products such as the Griffin PowerJolt SE will get the job done at a fraction of the price.
The real value of the DLO Transdock Direct is its structure. Dumping your iPhone or iPod in your car's ashtray or cup holder is no way to treat such a dignified device, and loose audio cables perpetually flopping out from your car stereo won't impress your date. Using the Transdock Direct, you can have your iPod set up in your car just the way you want it, keep your cables connected and tucked out of sight, and ensure that your iPod will be juiced up by the time you reach your destination.