If you’ve never visited WolframAlpha.com you are in for an interesting treat. This site is called a “computational knowledge engine”. It’s kind of like a mix of a scientific calculator, Wikipedia’s knowledge, and Bing. There is a goodintroductory video to help explain all the various things this site can do for you. Their site is also available as an iPhone app and Firefox plugin.
In this example photo, I compared the life expectancy in India (69.9 years) to that of Japan (82.1). While it might take a little time to learn the syntax of asking questions on WolframAlpha, there are LOTS of examples to help you.