A few months ago I stumbled across the very first Reverse GeoCache project by Mikal Hart. I was fascinated by the idea and decided to build one of my own.
What is a Reverse GeoCache?
Other than with ordinary GeoCaches you do not need to find the box at the target coordinate: You will already have it when the puzzle starts. But the box is closed and it will only open when you are near the target coordinate. In order to find the coordinate, the box has a button: When you press the button, the internal GPS receiver will detect the current location and the distance to the target will be displayed. Of course the number of trials is limited. If you press the button too often, the box will be sealed forever.