General   --   LC Classification -- Q
Science -- RefDesk
Martindale's Reference Desk
Database Advisor - UCSD -- use non-limited databases only
Science.gov

Astronomy   --   LC Classification -- QB
Astronomy - Wikipedia
Astronomy - Google  
Astronomy - Yahoo
Astronomy - Academic Info

Biology   --   LC Classification -- QH - QR
Biology - Wikipedia
Biology - Google
Biology - Yahoo
Environment & Nature -- Ref Desk
Biology Links -- Harvard U.
Biotechnology -- WWW Virtual Library

Chemistry   --   LC Classification -- QD
Chemistry - Wikipedia
Chemistry - Google
Chemistry - Yahoo
Chemistry - WWW Virtual Library 
Material Safety Data Sheet  - Wikipedia 
Where to Find MSDS
Material Safety Data Sheets -- U. of Vermont
Analytical Sciences Digital Library

Geology   --    LC Classification -- QE
Geology - Wikipedia
Earth Sciences - Google
Earth Sciences - Yahoo  
Geodata Information Sources -- U. of Iowa  
Sideling Hill, MD
Geology List -- U. of Cincinnati 
Geology -- Academic Info
Virtual & Online Geologic Field Trip...
National Atlas - USGS
WV Conservation Agency Map Viewer

Mathematics   --   LC Classification -- QA (includes Computer Science)
Mathematics - Wikipedia
Math - Google
Math - Yahoo
Mathematics - WWW Virtual Library
Mathematics - Academic Info
Martindale's Virtual Math Center

Physics   --   LC Classification -- QC
Physics - Wikipedia
Physics - Google
Physics - Yahoo
Physics - WWW Virtual Library 
Virtual Physics Center -- U. of California, Irvine
Physics - Academic Info