It is not exactly a search engine. The developers call it a Computational Knowledge Engine. Stephen Wolfram, physicist and company CEO, describes it as a synthesis of the worlds knowledge in computable form. It is Wolfram|Alpha.
Type Tulsa in the search box and you might get the elevation, the population, the weather and the current time. It will solve math problems and do calculations. Although it has far to go, it already has ten trillion pieces of data and more than 50,000 algorithms.
Take a look. Try a few of their examples and then make up some of your own. See if Wolfram|Alpha makes it on to your list of favorite web resources.