US Census Bureau
U.s. Census Bureau: Population Clocks
This U.S. Census Bureau Web site has two population clocks with notes available. One clock shows the population increase for the United States. The other shows the world population increase.
Columbia University
Nasa: Sedac: Urbanization and Human Settlements
[Free Registration/Login Required] A collection of twenty data sets from SEDAC (Socioeconomic Data and Applications Center) that examine urbanization in major metropolitan areas of the United States in the late 20th and the early 21st...
Columbia University
Nasa: Sedac: Applications of Satellite Remote Sensing
[Free Registration/Login Required] A collection of twenty-eight data sets from SEDAC (Socioeconomic Data and Applications Center) that examine ways in which remote sensing by satellites gives us useful information about the world....