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Eric Weisstein's Treasure Troves of Science

FirstGov for Science

Geode (Earth Science)

Intute: Science, Engineering & Technology - Also known as Physical Sciences Information Gateway.

Science Animations: Movies & Interactive Tutorial Links

ScienceNOW

ScientificCommons

Scientist Solutions

Scirus

Scitopia.org - integrating science and technology research

Voice of the Shuttle: Science, Technology, & Culture

The Why Files: Science Behind the News

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The National Academies

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ISI Highly Cited

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The Newton Project

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Thomas Edison Home Page