If you want to move a ball from one place to another, you have several options. You could roll it. You could bounce it. Or you could lob the thing. Any of these tactics would move the object along. But none would be nearly as fun—or as delightfully, needlessly complicated—as nudging it through a Rube Goldberg machine. These homemade gizmos, named for the 20th-century cartoonist and inveterate tinkerer, are thrillingly convoluted chain reactions. They’re spectacularly inefficient and superlatively mesmerizing; that’s the whole point. They’re also a great way to grease…
