When a criminal who called himself Penny Plunderer started operating in Gotham City, Batman deduced that he would strike at the local coin exhibition. The Plunderer was obsessed with Pennies and on the exhibition, there was a giant-sized penny, which was the Plunderer's target along with the first one-cent stamp in history. Batman confronted the Plunderer and used the giant penny to defeat the criminal and his henchmen. It is yet unrevealed how exactly did Batman acquired the Penny, but after his victory over the Plunderer, Batman took the giant coin to the Trophy Room of the Batcave, where it has become one of the main features of the place.Shortly afterwards, a criminal called Wolf Brando broke into the Batcave and confronted Batman and Robin. The villain used some of the trophies in the Batcave to his advantage and he tried to crush Robin using the mechanical dinosaur. Batman was forced to act fast and he used the Giant Penny to stop the giant robot from crushing Robin. Because of this, both the dinosaur and the penny were seriously damaged. However, both trophies were repaired and back on their places in a short time.
The Giant Penny was later used as a jamming signal disruptor during the week in which Batman wasn't allowed to set foot on Gotham City and he started operating on a flying batcave. The Penny was storaged on the small trophy room of the flying batcave and it proved useful on their crime fighting from air.
During the fight with Bane in the Batcave, the penny was used as a weapon. Bane pushed Batman against the giant penny, causing it to lose balance and fall on top of the hero, causing great damage.
When Nightwing returned to Gotham, he started the reconstruction of the cave along with Alfred and Tim Drake. Robin found the penny laying on one of the deepest and darkest areas of the cave. Using a harness, they lifted the penny to the main area and placed it back on its normal place.
DC Animated Universe
The giant penny was a staple backdrop piece in the Batcave in Batman: The Animated Series. The penny was once a deathrap tool utilized by Two-Face. On one adventure, Two-Face and the "Two-Ton Gang" captured Batman and tied him down to the giant penny. The penny rested on an over-sized coin-flipping machine. Two-Face boasted that if the coin landed on its bad side, then the Batman would be crushed, but even if it landed on its clean side, the impact would break every bone in Batman's body. Two-Face activated the flipping device and the penny sailed through the air. Fortunately, Batman had managed to pilfer Two-Face's lucky coin and used the jagged edges to cut through his ropes. The heavy penny instead landed on two of the villain's fleeing henchmen. 
- The Giant Penny along with the Mechanical T-Rex and the giant Joker playing card are the most iconic and recognized trophies in the Batcave. All these elements where created during the Golden Age of Comics, making them also a reminder of Batman's great history, even in modern times.
- The Giant Penny has to be kept polished to prevent corrosion. Batman and Robin were usually in charge of this chore, but in later years, it has become Alfred's duty.
- The Giant Penny is such a recognised part of the decor of the Batcave that variants on the theme can be found in similar bases: a Giant British Fivepence in the Knight's base, a Giant Wooden Penny in the Bat's Cave, and a giant false coin bearing the motto "In Stagg We Trust" in Batcave West.
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