WolframAlpha.com is the newest development by Stephen Wolfram. It is an “answer engine” as opposed to a search engine. It’s used to compute answers to questions. Being the idiot that I am, I couldn’t think of anything mathie to type in, so I opted for: “Why did the chicken cross the road?”:
In all fairness’s actually a pretty sophisticated tool that can tell you
all sorts of information about science, math, technology, geography,
weather, cooking, business, stocks, travel, music, and much much more.
It uses built-in models of fields of knowledge,
complete with data and algorithms.