My first Web 2.0 project. Not sure anyone wants it but the design came in to my head, so...
So many people have digital cameras, pretty much everywhere... but there's no infrastructure to harness that. Flickr Maps http://www.flickr.com/map/ can be used to find pictures in many places, but only those that have already been taken and geolocated (often manually.) (Flickr claims 15 million geolocated pictures, out of around 450 million.)