I heard a story of Seymour Cray doing a demo of one of the machines and it turned out there was a bug in some hardware procedure. While the customers were at lu

I heard a story of Seymour Cray doing a demo of one of the machines and it turned out there was a bug in some hardware procedure. While the customers were at lunch, Seymour opened up the machine, redid the wire wrap and had the bug fixed when they returned. (Note that many details are likely inaccurate as this is a 35-year-old memory of a second-hand story.)