Awhile ago, my wife gifted me with a Belkin TuneFM for my iPod nano. Pop the TuneFM into the iPod and optionally into your car’s power outlet and viola! You can use your car’s FM receiver to transmit music from your iPod over your car’s speaker system.
The longer the drive the greater the benefit of not having to exchange CD’s. On the other hand, the longer the drive the greater chance that the ideal FM frequency you begin with won’t be ideal for the duration of the trip.
There are already numerous mashups that leverage Google Maps (e.g. open houses on the real estate market in a particular neighbor, etc.). So, it seems possible at least to take driving direction data from Google Maps (or MapQuest et al), combine it with FM frequency data from Radio-Locator (or Sirius et al) and produce a trip-long, location-aware FM frequency recommendation service. For extra credit, this mashup could produce a script that could be imported into your GPS device (e.g. an audio script: “change FM frequency to 92.9 in one mile”).
I wonder how easy or difficult it is to build such a mashup.
Update 9/2/2007: The approach taken by Mark Snesrud and Bob Mayo to decode the “San Jose Semaphore” is inspiring.-Craig