Thinkbase

"Thinkbase is a new way to navigate and explore information on the web. It is what we call a 'Visual Wiki'. It is based on Freebase, an open, shared database of the world's knowledge - in other words a Semantic Wiki. Thinkbase uses a visualization tool (Thinkmap) to create an interactive visual representation of the semantic relationships in Freebase."

http://thinkbase.cs.auckland.ac.nz/