Am I where I am?

For the last month I have been experimenting with the location-based social networking tools Gowalla.com, Foursquare.com and Yelp.com.



At their most basic, each of these services allows you to check in to a location (restaurant, store, theater or other business), using your mobile device. Because the phone knows where you are through it's internal GPS, you can only check in to a location when you are within a certain distance, and cannot check in from your computer.



Why, you may ask, would you...