Computer Networks - The Heralds Of Resource Sharing (Arpanet, 1972)
https://archive.org/details/ComputerNetworks_TheHeraldsOfResourceSharing
In 1972, Bob Kahn was "arranging for a professional film crew to create a thirty-minute-long 16mm movie explaining the Arpanet, complete with an electronic-synthesizer soundtrack to set an appropriately futuristic mood." -- #MitchellWaldrop in "The Dream Machine (2001)
Mike Amundsen