GURPS Illuminati University actually has several Department of Redundancy Departments.
Naturally, Alpha Complex in Paranoia actually has a Department of Redundancy Department.
And many other variations on the theme. "Oh, this is the Complex Supply Bureau. You want the Bureau of Complex Supply."
An actual RPG session incident, when the GM wanted to make a particular detail very clear to the player: A female soldier with a rifle, pointed at you. She's wearing a green-camo uniform, complete with a rifle, which is pointed at you. The rifle appears to be a high-caliber automatic, and is pointed at you. The soldier is guarding this position, and is pointing her rifle at you. From a cursory study, she appears to be hostile — evidenced by the fact that she has a rifle pointed at you. She commands, in an aggressive tone, "Put your hands up! I have a rifle pointed at you!" Also, she has a rifle pointed at you.
It doesn't always work though. In one recorded instance, a Tabletop Game/Shadowrun party crawling through an oil pipeline was subtly warned four times about all the oil in the oil pipeline, but that didn't stop them from lighting their blowtorch. (One character survived the explosion but was knocked out and drowned in the harbor outside.)
The chant of the chaos marines "Blood for the Blood God" and "Skulls for the Skull throne".
Special character Canis Wolfborn is a Space Wolf, a Wolf Guard in Harald Deathwolf's Great Company, Lord of the Wolfkin, was literally Raised by Wolves, wears a wolf tail amulet and a wolftooth pendant, and rides a Fenrisian Thunderwolf into battle. This and similar examples led to a minor meme where random nouns and names are replaced with WOLF WOLF WOLF.
In the fantasy world Glorantha (featured in, among other things, the RPG Rune Quest) the local equivalent of China is bordered by the Shan Shan Mountains. In one Chinese language - I have forgotten which - "shan" means mountain. So they are the Mountain-Mountain Mountains. Did we mention that they are really high and impassable?
Due to some confusion when he first introduced himself, Ravenloft's most infamous lich is referred to as "Azalin Rex" in official court documents of his domain of Darkon. Invokes this trope, as "Azalin" is actually a mangling of his old Oerth title of "Wizard-King", thus making him Darkon's "Wizard-King King".
In the RPG Orbital, one space ship has "two emergency low berths for emergency use", and in outposts, "Individuals or teams will be regularly rotated back to the main installation on a regular basis".
