A Pythagorean Cup, also known as a greedy cup, is a drinking vessel designed so that if liquid is poured above a certain level, the entire contents drain out through a hidden channel. Invented by the ancient Greek mathematician Pythagoras, it serves as a practical joke or a lesson in moderation. In cybersecurity and technology, the Pythagorean Cup is often referenced as an analogy for mechanisms that enforce limits or prevent excessive use, illustrating how exceeding safe thresholds can trigger automatic safeguards or penalties.