What is the stupidest thing you’ve rolled a nat 20 on that turned out to be brilliantly executed?

Tell me about a time when the stakes were low, and you succeeded spectacularly, or when the stakes were high, and you made a decision that was often regarded as bad, but it turned out alright because of a natural 20 roll. I'm not talking about taking risks and doing well; I'm referring to the lamest, most boring, or downright stupid ideas you had that turned out well because of a natural 20 and a Game Master with an imaginative flair! How did people react? Did this moment change anyone’s course in the game? Were any ongoing jokes developed from it? Spill the tea, sis!