geotagging

I first came across this concept at Burning Man 1999 where Cap'n Crunch (AKA John Draper-yes, the guy who invented the infamous "blue box" and phone phreaking) introduced me to some of the thinking behind location-aware communities, and just what kinds of great information can be had about a place one visits. I am still missing a management tool for the user generated content for this application. Anyone know of anything in this area?