The sound of Number 5's laser firing is the same effect as the Ghostbusters' Proton Packs powering up.
Filmed in the town of Astoria, Oregon, where Free Willy, The Goonies (1985) and Kindergarten Cop (1990) were filmed as well.
As per the movie's attempt to portray a living robot in the "real world," every part of Johnny and his brethren was built to have a specific, logical purpose behind them. This was originally a source of contention between director John Badham and the robots designer Syd Mead, the latter of whom insisted on giving Johnny "eyes" to give the character a method of visually expressing emotion. As a result, Johnny's iconic "eyelids" were created, with the explanation that they were sun guards and camera coverings.
At the point where Number 5 first hears the El DeBarge song "Who's Johnny" while driving the Nova van, the original choice of song for that section was the Dire Straits song "Money For Nothing," but unfortunately getting the rights to use that song was deemed to be too costly.
Three interchangeable radio-controlled heads were built for Number Five so facial expressions could be properly articulated according to the scene.