Powerset Search Engine

is a new search engine that uses artificial intelligence to locate relevant article. I found Powerset is fairly intuitive to use, but it will require a LOT of venture capital before the scope of materials indexed is as wide as Google's. Presently the content is mainly from Wikipedia. For each document, Powerset displays a floating article outline (table of contents) which makes usage of the document at hand easier.
_-D.D.