Most gaming groups tend to accumulate these over months or years of play.
Many editions and supplements of Mekton have featured mecha pilots with similar names asking their (also similarly named) techs to build them either six-armed Humongous Mecha (because they "got a very good deal in a half dozen beam swords") and/or smaller infiltration units designed to look like a Coke vending machine ("It even gives change!"). They are also invariably hit on the head with a large wrench for their efforts.
Bjorn the Fell-Handed is the oldest Space Marine in existence, and remembers walking beside the Emperor and his Primarch ten thousand years ago. His chapter keeps him in stasis for his own safety, waking him up when they need spiritual guidance. Fans quickly noticed this is basically the same as "waking grandpa up up when they want to hear stories".
Every version of Munchkin mentions in its rules that all players start as "a level 1 human with no class.(hehe)", or something similar (such as "a level 1 human with no class and no style" in Munchkin Fu). Later additions tend to follow this with a remark like "We never get tired of that joke."
The Pacifist from Cosmic Encounter has sort of become the default choice when the art for an alien shows them interacting with another alien.