The Rickey Henderson/John Olerud story is an all-timer for me.
In spring training 1999, Rickey Henderson of the Mets was reunited with first baseman John Olerud, who had been his teammate with the Blue Jays six years earlier. As most people know, Olerud had an aneurysm in college, which required brain surgery. So to protect his head, he was allowed to wear a helmet in the field. As the story goes, Henderson was talking to Olerud one day, noticed the helmet and said “You know, when I played in Toronto, we had a guy who wore a helmet.”
“Rickey,” said Olerud, “that was me.”
The story being totally made up hasn't changed my opinion, either.