General Reference

• Answers.com - "Offers free access to millions of topics from the world's leading publishers."
• eHow: How to Do Just About Everything - A how-to site that covers the gamut.
• How Stuff Works - Learn about the way things work, from computers to the human body.
• Library Spot - Acronyms, almanacs, calculators, dictionaries, encyclopedias, maps, style guides, and more.
• Martindale's The Reference Desk - A useful general reference site.
• National Geographic Maps - Find a map for any place in the world.
• Refdesk.com - One of the most comprehensive reference sites on the Internet.
• Sparknotes - Consists of guides compiled by Harvard students. Originally a collection of literary notes (similar to Cliff Note), now it includes notes for all subject areas. All notes are online and free, but the "printable" versions cost money.