Geolocation spoofing with Windows 8 Simulator
While working on a geo-location application, you would want to see how your app works for different coordinates.
Windows 8 has a very helpful simulator that makes testing your geolocation based web application or Windows 8 Store app, easy.
The Windows 8 Simulator exe can be found at this path (assuming your system files are in the C Drive): C:\Program Files\Common Files\microsoft shared\Windows Simulator\11.0
The Simulator can also be invoked through Visual Studio 2012.
Update: I noticed that this tool is available after you install Visual Studio 2010 Express for Windows 8 or VS 2012
Windows 8 Simulator
To change the default location's coordinates, select the Location icon in the Simulator & fill the latitude and longitude of the place you want to test your app for.
Update(29/Dec/2013): Chrome & IE11 now allow you to spoof latitude and longitude coordinates from their respective Developer Tools
Happy geo-location spoofing!
Related: Using the Windows 8 Simulator & VS 2012 to Debug the IE10 Touch Events and Your Responsive Design