Feynman has no dearth of stories showing his genius, but one specific example is a video 3Blue1Brown did of how Feynman converted the velocity vectors of a revo

Feynman has no dearth of stories showing his genius, but one specific example is a video 3Blue1Brown did of how Feynman converted the velocity vectors of a revolving body in a gravitational well (I think it was that) into a perfect circle of vectors. It's one of those results that's deep and yet you can find it yourself too if you spend enough time with it.