Directories

Roget's International Thesaurus

Zip Code Look Up

Area Code Locator

AnyWho: Finding People, Places and Businesses  

Language

Bartleby.com
Literature sources including quotations, essays, poetry, short stories, the King James Bible, Shakespeare, Gray's Anatomy and more.

Merriam-Webster
Online Dictionary from Encyclopedia Britannica

Dictionary.com

Portals and Search Engines

Infomine
Search Engine for Scholarly Internet Resource Collections

Internet Public Library
Collections of websites for information, reference and research

Virtual Reference Shelf
Library of Congress