Wolfram|Alpha - Computational Knowledge Engine

Wolfram|Alpha is a computational knowledge engine being developed by Wolfram Research. The project was announced in March 2009 by Stephen Wolfram. Wolfram|Alpha will officially launch May 18, 2009 as "one simple input field that gives access to huge system, with trillions of pieces of curated data and millions of lines of algorithms."

Its mission is "To make all computable, factual knowledge available to everyone".

I think Wolfram|Alpha is going to be a serious contender to Google search engine.

WolframAlpha - Computational Knowledge Engine
http://www.wolframalpha.com/index.html

Watch a Quick Introduction to Wolfram|Alpha
http://www.wolframalpha.com/screencast/introducingwolframalpha.html