Well, it _is_ off topic, just the example I show here is not.
Just go to http://www.touchgraph.com/TGGoogleBrowser.html and enter "www.hpmuseum.org" (w/o quotes), hit 'Graph it!', wate some seconds to get a topic map about the subject. It is functional as with two clicks you are on the shown site. Quite nice.
Ciao.....Mike