Nearby Friends is a new Facebook application which taps into the recently launched Facebook Places check-in service to locate all your Facebook friends plotted on a Google Maps interface. The app, a simple tool that places Facebook profile photos as a pin on the map, doesn’t limit itself to where your friends are right now, it actually displays their entire Facebook check-in history, as lines traversing the map. With the app installed, you can actually track a friend’s travels, easily identifying their favorite hangouts, daily treks, their workplace and more. Is this the first Facebook Places cyber-stalking tool? Or just a handy way to see what your friends are up to?