Eric Weisstein's Treasure Trove of Physics - Online encyclopedia of physics terms and formulas. Full searchable, and also browsable alphabetically and by topic. Part of Eric's Treasure Troves of Science.
The Net Advance of Physics - MIT resource providing discussions at various levels of sophistication that cover all areas of physics.
The Physical World - Answers to simple physics questions, from New Scientist.
Physics Central - Find out how physics is part of your world. We answer your questions on how things work and keep you informed with daily updates on physics in the news. We describe the latest research and the people who are doing it and show you physics in action.
Physics Central - A page on modern physics, such as quantum mechanics and black holes, and some mathematics.
Physics News Graphics - Diagrams (with captions) appearing in various AIP publications, sorted by category or by date.
Physics on MathPages - Articles, leaning towards a mathematical description, on a wide range of topics in physics.
Physics Post - A tutorial and article driven community. Votes, science news and a discussion forum.
Physics Today - The flagship publication of the American Institute of Physics (AIP). Provides feature articles, news stories, analyses, book and product reviews, a searchable job database, and obituaries.
PhysicsWeb - Physics news, jobs, equipment buyer's guide, and events.
PhysLINK - Links to physics departments, physical societies, journals, job information, and other physics related information.
Physnet: The Physics Departments and Documents Network - Serves information from physics departments and institutes worldwide: departmental information, locally stored documents, authoring tools, free access journals, jobs, conferences and education material.
PhysOrg.com - Physics news, semiconductor technology news, space news and a scientific forum.
Usenet Physics FAQ - sci.physics frequently asked questions with answers.
What You Want To Know About Physics - Summarizes in simple language, without advanced mathematics, the foundations of physics. The index gives direct access to selected topics.
World Year of Physics 2005 - International effort to celebrate the 100th anniversary of the Miraculous Year (1905) and raise public awareness of physics.