I think most people are familiar with this scenario (either first hand or via media). The PCs are going off the rails, the GM gets fed up, and then suddenly,
Rocks fall, everyone dies
This is more than just a GM punishing "bad" players. This is a very specific expression (it even has a TVtropes page), and when repeated verbatim conveys a lot more information about the context than the 4 individual words normally would.
Where did this expression come from? When was it popularized? TVTropes notes that it was used in the original Tomb of Horrors module in 1975, but that it was probably in use much before that. Is there any original source for this?