Check out gapminder.org, a wonderful statistics visualization site. For example, there is this: CO2 emissions since 1820

CO2 emissions in 2000 by country
If you go to the link above, you can animate this image, seeing how the per country CO2 changes over the period 1820-2000. The area of the circle is proportional to the country’s annual CO2 emission per capita. Mouse over circle to see name of country. Gapminder.org has a wealth of great databases and visualizations thereof.
Note. I am so impressed with Gapminder.org — their mission and their effectiveness — that I would like draw your attention to this quote:
Building a fact-based world view
Gapminder is a non-profit foundation based in Stockholm. Our goal is to replace devastating myths with a fact-based world view. Our method is to make data easy to understand. We are dedicated to innovate and spread new methods to make global development understandable, free of charge, without advertising. We want to let teachers, journalists and everyone else continue to freely use our tools, videos and presentations.
Your contribution will help us in our efforts to explain how the world is changing. Your generosity will strengthen our independence.
Help us achieve a fact-based understanding of the world. Support our work by making a donation today.
Donate to Gapminder.org