A computer program such as GNU Mailman, LISTSERV or Majordomo that re-mails electronic mail to a pre-determined distribution list

Neutron reflector

Reflector, The newsletter of the Boston section of the Institute of Electrical and Electronics Engineers.

Reflector, a device that causes reflection (for example, a mirror or a retroreflector)

Reflecting telescope

Reflector, a Decepticon in the Transformers toyline of the 1980s.

Reflector the part of an antenna that reflects radio waves

Reflector, a 2000 album by Killing Heidi

Reflector, a 1981 album by Pablo Cruise

Reflector, a 2002 album by PlanetShakers

Reflector, a component of some rotor machines (a type of cipher machine), such as the Enigma machine, that sends electrical impulses that have reached it from the machine's rotors, back in reverse order through those rotors.

The .NET Reflector code browser utility

In photography, a reflector (photography) is used to control lighting contrast