As an individual who is not a fan of Wal-mart and its destruction of independent stores across the U.S. I can only describe this map animation as an example of a viral epidemic spreading across the country. Melodramatic introduction aside, this map animation is a wonderful example of how to visualize spatial-temporal dispersion. The map animation was created by Dr. Thomas Holmes of the University of Minnesota department of economics. In order to view the map animation in its "everyday low prices" goodness you will need WMV. Enjoy.