If you like man trivia (and why else would you be reading this?) you could check out the top comment at https://unix.stackexchange.com/questions/405783/why-does-man...
(discussed at https://news.ycombinator.com/item?id=27994194)
"The developer of the man-db, Colin Watson, decided that there was enough fun and the story won't get forgotten"
Haha! Adequate amount of fun was provided, please resume regular man activities.
Reading this makes me wonder if Easter eggs are ever appropriate for something as ubiquitous as man.
A great innovation over simple AB testing
Another fun related one: If your username is Tyler and you run shutdown, instead of the usual message it will say "Oh, good morning Mr. Tyler, going down?"
Discovered this in college when I was shoulder surfing a coworker who always used the username Tyler. When he typed shutdown I called it out, and he said, "wait, it doesn't do that for you? I always assumed it said that for everyone and just replaced the username!".
(For those of you too young to know, it's a reference to an Aerosmith song)