Wikimedia just announced an open standards based means for adding geodata to any article. They launched a new Wikimedia extension supporting user added geo-location data. And once added to the system, all of it is accessible via the WikiMedia API. This allows sorting and searching of the Wikipedia by global coordinates.
One of the first experiments of this in action would allow a smartphone versions of Wikipedia, to sort and show you all articles relating to wherever you are.
Sounds incredibly useful, can’t wait to see this evolve.