Ford Motor Company has realized that it is possible to extend the functionality of a car with the devices that the user brings into it. Instead of building in functionality that may become obsolete before the car, it is better to leverage the user’s devices, such as cell phone, mp3 player, etc. For instance, the car can use the cell phone to connect to the Internet instead of duplicate functionality.
This is a very good example of a limited and specific version, for a small set of applications, of what a Personal Network could provide.