Scott Watson's Physics FAQs - A list of FAQs (Frequently Asked Questions) regarding Cosmology, String theory, Relativity and General Physics
Advanced Physics Forums - Intended primarily for physics majors, graduate students, postdocs and faculty. Get meeting information, theoretical and research information and exchange of ideas. Meant for the physics community throughout the world.
Groupsrv.com - Physics Forum - Discussion for scientists.
PhysOrg Discussion Forum - Applied physics, nanotechnology, quantum physics, and semiconductor technology. Also discussions of the latest physics news.