"GPS" device & connections Instead of using the satellites like Google Maps, is it possible to come up with a device that any device, such as mobile and laptops can connect and communicate with the device? In other words, let say Harvard campus. We know its campus is very large in terms of area covered. If I want to make an interactive map for Harvard, both street and inside of buildings (meaning you can also keep track of your location inside the buildings, floor by floor, room by room), what kind of connection is preferable? Bluetooh (class 1 is only about 300 feet max), and wifi is never a considerable choice. Thank you.