The NIST Reference on Constants, Units and Uncertainty  
   Values recommended for international use by the Committee on Data for Science and Technology, International Council of Science. Navigation is by text search.
   http://physics.nist.gov/cuu/Constants/

The Laws List  
   An alphabetical glossary of the various laws and theorems in this science.
   http://www.alcyone.com/max/physics/laws/

Physics Formulae  
   A collection of frequently used physics equations compiled into several downloadable formats.
   http://www.xs4all.nl/~johanw/contents.html

Physics FAQ (Where to Find It)  
   Links where to find the FAQ documents for physics.
   http://www.faqs.org/faqs/physics-faq/where-to-find-it/

Eqndb  
   Search for physics equations and constants by keywords and symbols.
   http://www.eqndb.com

The Physics Reference  
   Site contains every formula a first-year physics student is likely to run into.
   http://dph1701.tripod.com/physsci/

Physical Reference Data  
   Held at NIST Physics Laboratory.
   http://physics.nist.gov/PhysRefData/