BBC’s Country Profiles

CIA World Factbook (Country profiles)

World 101 (Region profiles, overviews, and links to articles)

International Monetary Fund (Economic data on countries)

The True Size (compares actual sizes of countries)

Constitute (compiles constitutions from different countries)

American Panorama (Historical atlas) 

US Department of State (Focus on US/Foreign relationships)

World Atlas

Gapminder Tools (for graphing demographic data)