One of the new features added to Windows 7 is it's Sensors and Location Platform that allows Windows and your applications to know exactly where they are so they can provide more local and relevant information. Microsoft uses the example "[a]mbient light sensors, for example, can allow your computer to automatically adjust your screen's brightness based on the current lighting conditions." Users can add "sensors" to Windows to give it these capabilities.
When I came across this Lifehacker article covering a free sensor called Geosense I had to download and install it. So I did, then I enabled it in Control Panel > Location and Other Sensors and that was it. I set my weather gadget to find my location automatically and it did.
At first I installed it on my work computer. It didn't work - most likely because of our network infrastructure, in which case it said I was in Beverly Hills, Ca - ha! But it works great on my laptop and now I don't have to worry about changing my location as I travel.
After everything was configured I changed who can access the sensor so that only my specific user account could. Call me paranoid, but I like to know who's tracking me and when.