How about conceptual searches? (Score 1)

A big problem with Google is that it can only retrieve web sites that have the exact search term. Type in "automobile manufacturers" and you won't find a single website for an auto maker. That's because those sites don't use the term, even though sites that point to them might.

There's a way out of this, though. Jon Kleinberg of Cornell describes an interesting application of graph theory to the Internet to yield better searches where the search term may not even be present.

I've written an article and a program to demonstrate the technique at Mathematics of the Internet.