The Dot and the Line, Chuck Jones/MGM's classic 1965 Oscar-winning short film based on Norton Juster's 1963 book The Dot and the Line: A Romance in Lower Mathematics inspired by Edwin Abbott Abbott's 1884 novella "Flatland: A Romance of Many Dimensions." When I was a kid and this came on between Tom and Jerry episodes, it blew my mind. Still does. (Thanks, Kathy Cheun!)
David Pescovitz is Boing Boing's co-editor/managing partner. He's also a research director at Institute for the Future. On Instagram, he's @pesco.