The history of flexagons

So, you know now that flexagons were invented by the British mathematician Arthur Stone, while he was still a graduate student in math. Together with other notable mathematicians and physicists, John Tukey, Bryant Tuckerman and Richard Feynman they studied flexagons and the math behind them, and we’re going to follow in their footsteps.

Discussion

As you saw, flexagons were discovered by chance. Do you know of other discoveries that were made by chance?