The Longest Most Meaningless Movie in the World (1968)

"'The Longest Most Meaningless Movie in the World' is an underground movie made in the UK that runs to 48 hours long. No actual footage was shot for the project, which instead consists entirely of outtakes, commercials, strips of undeveloped film, Academy leader, and other filmic castoff material, creating a seemingly endless stream of newsreel and stock footage. It was the longest film ever made at the time of its release, but has since been superseded by many other films."