But how did you know...?

Just logged in from my hotel, and loaded some mapping software to check a route. And up comes my location. How does the mapping software know where I am when I don't have any GPS hardware plugged in? Suddenly remember that this is Microsoft software, which has some sneaky code that looks at IP address, locally visible wifi networks and can sometimes use this to work out where you are. Still, a bit scary when you aren't expecting it. What would someone make of this if there weren't tech aware? Probably convince you that the computer was posessed. Suddenly starts to explain why there are all these idiots on youchoob cutnpasting comments about "you must repost this five times in the next hour or you will dye!". etc.