I remember a friend telling me about a contest between my Dad and a computer in the 1970s.  Some calculation needed to be done at work and it needed to be done quickly.  Dad did it faster than the computer - all in his head.  His co-workers were so amazed.

Of course his co-workers were incredulous.  Because they couldn't believe it, they continued to test Dad vs. the computer.  He got faster and faster.  No matter what they threw at him, he always beat the machine.  No one challenged Dad after that.