Gapminder - visualizing statistics about the world
This is by far one of the coolest visualization tools out there. And not because of slick design or sophisticated visualization algorithms - it is the idea itself that makes this tool so great. It's called GapMinder.
Founded by Swedish professor of international health, Hans Rosling, this tool is aiming at visualizing international statistics into moving objects on a graph. The backend database holds vast amounts of statistical data about economics, health, education, population and demographics and more. The tool allows visualizing progress over years of the user chosen data over a two dimensional graph.
The software behind this great tool is called Trendalyzer. It was acquired by Google in 2007. Some parts of Trendalyzer became available to the public as part of the Google Visualization API
Watch this video if you want to really experience the greatness of GapMinder, and the greatness of the man behind it.