Physics and Astronomy Forums  
   A series of different threaded forums for discussing famous people as well as topics related to astronomy and astrophysics.
   http://astronomyphysics.com/

Theoretical Physics  
   Archives of an discussion group for discussing related topics.
   http://research.spinweb.com/

Physics Forums  
   Bulletin boards on physics and related subjects. Includes related polls and a list of active threads.
   http://www.physicsforums.com/

Scott Watson's Physics FAQs  
   A list of FAQs (Frequently Asked Questions) regarding Cosmology, String theory, Relativity and General Physics
   http://www.het.brown.edu/people/watson/pages/resources.htm

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.
   http://www.advancedphysics.org/

Groupsrv.com - Physics Forum  
   Discussion for scientists.
   http://www.groupsrv.com/science/viewforum.php?f=1

Physics & Astronomy Discussion Forums  
   Discussion forums devoted to physics & astronomy, with a concentration on eletricity and magnetism.
   http://physicsastronomy.com/

PhysOrg Discussion Forum  
   Applied physics, nanotechnology, quantum physics, and semiconductor technology. Also discussions of the latest physics news.
   http://forum.physorg.com/