Finding the right FM channel!

This is really my favorite third-party iPhone web application. Since many cars don't have the best iPhone/iPod integration, using an FM transmitter is sometimes the only way of getting the music in your car speakers. The huge problem with an FM transmitter is always to find the right frequency that is not in use by any radio station. The problem gets harder in large cities. This website will let you enter a zip code and it will give you a list of the best possible unused frequencies! You can check it out at http://dlo.com/openfm/