Physhare  
   An unmoderated listserv dedicated to precollege physics education. Archives since 1991 are searchable.
   http://geocities.com/physhare/

PHYS-L  
   Email list for physics educators with about 700 members and typically 5-50 messages per day. Online archives (for posts since 1996) and membership interface available.
   http://physicsed.buffalostate.edu/PHYS-L/

TAP-L and PIRA  
   Frequently asked questions regarding the physics demonstration-related listserv TAP-L (Teaching APparatus) and the affiliated organization called PIRA (Physics Instructional Resource Organization).
   http://www.wfu.edu/physics/pira/

Institute of Physics - Email Discussion Lists  
   Descriptions of and instructions how to subscribe to IOP lists: Physics Early Professional Development (PEPD), Physics Teaching News & Comment (PTNC), Scottish Physics Teaching News & Comment (SPUTNIK), Northern Ireland Physics Teachers Group (NIP
   http://teachingphysics.iop.org/teacher_support/email/index.html