Maptor is a concept device that uses an inbuilt projector to throw a map of the current location on to a surface. It's small enough to be worn around the neck. It has built in GPS that can track exactly where you are and then download the appropriate map and your favourite points of interest that are also projected.
The downside of this concept device is the projector. As of now there really isn't a projector of such a small size that could successfully be used in daylight. However, a company recently were seen to be creating portable laser projectors which could potentially have application in this design.
For now, we just have to enjoy the pictures below. The concept was designed by Jin-Sun Park and Seon-keun Park.