Encyclopedias, almanacs, dictionaries, statistics, and other sites for quickly looking up facts.
IllinoisAtlas.com: A collection of Illinois and U.S. statistical maps.
InfoPlease.com: Almanacs, atlases, and more.
OneLook Dictionary Search: Look up words in almost 1000 online dictionaries at the same time.
Wikipedia: "The free encyclopedia that anyone can edit."
World Factbook: The CIA's book of country profiles.
50 states- This site provides information about the 50 US states.