Wolfram Alpha was launched in May’09. Its not a search engine, its “answer” engine. It was made by Wolfram research, founded by Stephen Wolfram( child prodigy I must say, read about him on wikipedia ), a mathematician and physicist.
This site is amazing, it is an online service that answers factual queries directly by computing the answer from structured data, rather than providing a list of documents or web pages. You type in query like “e^2” and it gives you answers in graphs, value etc. if you type in “chocolate” it will give its nutritious facts. This site amaze me from the very first time I have seen it and to be more specific the answers it gives.
They have APIs waiting to be used and give some awesome website. You can create a Pro account for more benefits. I personally feel this thing can do something to internet what Hotmail did to email.