Which household electronics contain or used to contain photo multiplier tubes?
Sure, if you happen to have a 1955 Lincoln Continental with all the options kicking around.. they were used in the automatic headlight dimmer circuit. 


  OPERATION: With headlights turned on, and the pilot
  light indicating automatic control, light striking the
  photo-multiplier tube of the control assembly causes
  generation of a weak electrical current. This current
  is electronically amplified and used to actuate relays
  in the switch assembly


Otherwise, I think you'll find them very, very rare on the ground.