Bartlett's Familiar Quotations
The tenth edition of John Bartlett's quotation finder from the year 1919. The 11,000 quotations can be searched by keyword and author, chronologic and concordance indexes are also available to help you locate the quotes. Available from Bartelby.com along with Columbia Quotations and Simpson's Quotations.
http://www.bartleby.com/100/

A Short Dictionary of Scientific Quotations
Science quotes hosted by NaturalScience.com and edited by Alfred Burdett.
http://naturalscience.com/dsqhome.html

Movie Quotes
Find quotes from various films from the Internet Movie Database. Search by keyword, cast or crew member, year or decade.
http://us.imdb.com/Sections/Quotes/

The Quotations Page
One of the oldest quotation websites on the Internet, it was started by freelance writer and computer consultant Michael Moncur and continues to be maintained by he and his wife Laura Moncur.
http://www.quotationspage.com/

Quoteland.com
Search or browse this commercial site for quotes.
http://www.quoteland.com/

Women's Quotations
From Women's Media.com, a site devoted to women's self improvement, this site provides quotations by women by themes.
http://womensmedia.com/quote-a.shtml