The I-Rocks MP3 Car DJ FM transmitter takes the pain out of things by accepting an audio input from an MP3 player, Discman or other audio source (3.5mm stereo jack) and re-broadcasts this over a narrow FM radio band. All you need to do then is tune in your car's radio into the I-Rocks frequency and off you go -- instant MP3 player in your car.
It's not the first product of its type, in fact there have been many FM transmitters over the past half year that do the same thing, but the real differentiator with the I-Rocks unit is that it has a USB port on it. This turns any USB 1.1 or 2.0 memory key into a music store, and the I-Rocks acts as the controller. Considering the sheer number of USB memory keys on the market, this is an awesome feature. We tested it with a standard 128MB flash memory card and with a 5GB Seagate Pocket Drive and it worked wonderfully.
Powered by a cigarette adaptor on a hinged arm, the front of the I-Rocks transmitter has simple touch buttons for skipping forward and backward through tracks, pausing and playing. The lack of any form of LCD may dissuade some, but that's really asking for too much.
The I-Rocks is the perfect product if you've got lots of USB memory keys laying about, but haven't yet bought an MP3 player. There is an optional AC adaptor available so you can power it at home too, but as an in-car player it's excellent.