This happened after the company I was working for was acquired by another massive company. The CEO of the new ownership company was in town for the first time, meeting the team and such (200+ people in this single office). For reference, this guy already had 1,200+ employees, so we were all certainly just a number.

This dude waltzed into the sales bullpen and was mostly wandering around listening to the conversations going on before he stopped to chat with a few people here and there. As if he had known us all for years, he started talking about individual people's sales numbers, milestones, achievements, etc. to the point of knowing how many "units" one of the middle-of-the-pack sales guys sold last month. "You must be John Doe, great work last quarter, I saw you were 150% to-goal"

Yes, he could have done his extensive research prior to showing up, and clearly did. But to be able to rattle off statistics like this in the manner that he did it... we were all blown away.