Check out this really cool site that uses the Google API to display relationships based on the Google seach engine database. It’s called Touch Graph.
The specific use of Google can be found at TouchGraph GoogleBrowser. I like the people search found at google-set-vista. You can enter a person’s name and find relationship with other names, ideas, etc.
Update: 10.03.03
Found a new link related to TouchGraph:
http://www.pmbrowser.info/audioscrobbler.html