This chart shows where each search engine gets the main results it displays: http://searchenginewatch.com/webmasters/article.php/2167981
List of search engines: http://searchenginewatch.com/links/
http://kartoo.com/: KartOO is a metasearch engine with visual display interfaces.
List of directories: http://www.strongestlinks.com/directories.php
Open Directory: http://dmoz.org/
Exactseek: http://www.exactseek.com/
Starting Point: http://www.stpt.com/directory/
http://bubl.ac.uk/link/: organized according to the Dewey Decimal System
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