Geo Photography at the West Pier
First, you synchronise its clock with your camera's. You then let it track your geographical location while you take photos. Afterwards, you insert the camera's SD card into the slot and it encodes the photos with the appropriate locations.
The photos can be uploaded to Flickr, Panoramio, Picasa or elsewhere and they position themselves into the right place on the map.
I've used this image in an article on "Location-based publishing and services", published on Dev.Opera.