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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LandSerf is a free Geographical Information System (GIS). It's software for visualizing and analyzing various surfaces. Written in Java.

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