Searchable directory based on the ODP, combined with their own PageRank algorithm within each category.

WebDAV Resources - http://www.webdav.org/ a central resource for documentation, specifications, software, mailing lists, and other useful items.

US Census Bureau Geography - http://www.census.gov/geo/www/index.html Mapping products and services, as well as geography resources used to compile the US Census.

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CIA World Factbook - https://www.cia.gov/library/publications/the-world-factbook/ U.S. government profiles of countries and territories around the world.

e.g. "ajax apis" or "open source"

Much of the content in this directory was developed by other companies or by Google's users, not by Google. Google has not tested or verified the features or security of the third ...

Much of the content in this directory was developed by other companies or by Google's users, not by Google. Google makes no promises or representations about its performance ...

Google Maps Directory covering mashups, tools, resources, developers, websites about google maps

Speakout.com: Issues - http://www.speakout.com/activism/issues/ Library of online information and links related to (mostly U.S.) public policy issues.