A feature that is becoming increasingly popular in cameras is a GPS device capable of finding your location. The cameras also have an SD card which can hold map files, (free map files are available on the net), a good screen which can display maps, and community-made firmware.
I would be extremely happy if a basic GPS location mapping app was added to CHDK, compatible with cameras that have GPS functionality. An app that used the location data provided by the GPS device to map your location and display it on screen with a zoom and scroll function for the map. A very basic would be enough, it doesn't have to be detailed.