Fascinating collection of maps of the United States, showing per county races, religions, income, politics, etc. from various sources, especially the U.S. Census data. This graph shows racial ancestery.

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See the world mapped with each country expanded or shrunk based on various criteria. This example shows each country sized to reflect it's relative proportion of the world's population.

Other maps on the site show the world population 2,000 years ago, the total children, imports and exports of various commodities, etc. The site plans to add many new maps to their collection in upcoming months. (link from SchreiberBike).

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