Tagzania – Tags and Places
http://www.tagzania.com/

Tagzania is about tags and places. If you register and log in, you can add places, points, to create and document your maps. When you add a point, you may tag it with keywords. That way, Tagzania is not only a place to build and keep your own maps, shared territories are created as well. This has been added to the tools section of Research Resources Subject Tracer™ Information Blog.