With so much knoweldge out there, I often wonder why I may need to google something 5 times, trying 5 different keywords until I get everything I want. But with this tool (http://www.wolframalpha.com/) you get answers to factual queries directly, rather than providing a list of documents or web pages that might contain the answer. Ever since Wolfram Alpha was announced in March 2009 I have been looking forward to try it. It was released to the public on May 15, 2009 and I admit it won me over. Try it!
Some queries you can try:
a city (e.g. New York)
a math formla (e.g. x^2 sin(x))
a calculation (e.g. 5+2)
any date (try your birthday!)
types of food (e.g. pizza) – i was impressed with this one!
Have fun learning!