OK, this is really neat technologically. Or really freaky if you get the willies about people knowing where you are. Won’t matter that you don’t have GPS installed.
Some positioning systems make use of natural objects or phenomena; for example, celestial navigation uses the stars, compasses use Earth's magnetic field, and ancient mariners relied on trade winds. Other positioning systems rely on facilities or networks built for the purpose; for example, lighthouses, buoys, or Global Positioning System (GPS) satellites. Yet a third way is to exploit devices that were built and deployed for other purposes. That is what Skyhook Wireless is demonstrating, by implementing what it calls a WiFi positioning system (WPS). This new technique relies on the growing popularity, in U.S. urban areas, of wireless Internet access points and uses them as signals of opportunity to determine the position of mobile WiFi-enabled devices, such as laptop computers, PDAs, and cell phones.
In one sense it’s neat, in that you are locationally enabled, even though you don’t have a GPS, or if your GPS doesn’t get proper signals in certain areas in urban zones. On the other hand, if you are freaked out about people knowing where you are at all times, you have one more item of technology to avoid.