Characters inserting a tied coin into a coin-operated device and then pulling the coin out with the string to get a free item or service from the machine. However, this trope also extends toward other things.
Later in the 1980s, when video game arcade operators realized that people were doing this, manufacturers started putting a string cutter into the coin mechanism. If you tugged back to try to hit the switch again, the string would cross the cutter and be severed by it, thus capturing the coin and preventing its reuse by the crooked customer. In modern times, coin-operated machines simply have a one-way ratchet, preventing the return of any coin once it has passed the counting mechanism.
- One Carl Barks story features Donald Duck going to a valley to test echoes. His nephews set up a box where one can deposit a dime and expect an echo in exchange. The nephews just repeated whatever Donald said every time he put a dime in the box. It turns out that Donald was using the trick to get free echoes. They retaliate and eventually get the seven dimes.
- Kid Paddle tried this trick along with a variation: small discs of ice of the same diameter as a coin.
- In the 1920 movie The Scarecrow, Buster Keaton tricks the gas meter with a dime on a string.
- Yellowbeard: Commander Clement wants to get some information out of Harvey "Blind" Pew but doesn't want to pay for it. Each time he drops a coin into Pew's cup, he yanks it back out again with a string.
- Treasure of Swamp Castle: The guard is a victim of this trope used as bribery. Though it's done without string, two characters invoke this.
- In The Black Spider-Knight Leopold XVII, to take a chance at slaying a dragonnote the eponymous knight needs to go through an automatic toll booth first, and the fee is a pocket of gold coins. Jamming a sword in the money slot doesn't help because it has apparently been built to withstand this kind of abuse from this setting's knights, so Leopold XVII tries this trick. The string is immediately cut by built-in automatic scissors.
- Recruits to the Ankh-Morpork City Watch were once given a coin, the King's Shilling, and sworn in on it when they gave their oath of service. In modern times, however, the Watch has become so stingy and under-financed that (even though a shilling is no longer quite so much moneynote ) the officers have a shilling on a string to perform the tradition on the cheap. At once point Vimes (masquerading as a transfer officer from another city) twits an officer by grabbing the coin before he can pull it back.
- One Garfield strip made use of this trick with a cookie, instead of a coin.
- Muse of Hello Wandering Star is shown doing this in one strip. She isn't particularly "heroic".
- SCP Foundation: Some of the experiments done on SCP-261 (a seemingly ordinary snack vending machine that dispenses random snack-type items ranging from mundane to bizarre) used a coin on a string. The machine at first responded by dispensing seemingly normal food items that caused the eater to promptly vomit them up, and eventually ended by simply dispensing a live grenade. The Foundation stopped testing the coin-on-a-string trick after that one.
- Done in the 1937 short Magic on Broadway. This was part of Paramount/Fleischer Novelty-Cartoon shorts which featured animation in part of it and live-action in the other half. The cartoon half of this entry has a slot-machine player cheating the machines in a penny-arcade by tying a string to the coin and pulling it out again. The machines get rather animated about being cheated and the petty-gambler receives some rough treatment.
- Similarly in the 1939 Porky Pig cartoon "The Film Fan."
- Bender from Futurama is fond of the coin-on-a-string trick.
- The first time he uses it is in a suicide booth (What is he saving the coin for then?)
- In "The Duh-Vinci Code" he tries it with a giant coin. It tears his arm off.
- He does it again in "Lethal Inspection" when using a phone booth, in a similar manner to the pilot episode.
- SpongeBob SquarePants: Mr. Krabs uses the coin on a string on occasion, as in one flashback.
- Donald Duck's early films has him using this technique (a la Mr. Krabs) to economize at a fair.
- In "Donald's Happy Birthday", when Donald forces his nephews to put their allowance in a bank, one of the nephews tries to do this to keep his coin, but Donald was one step ahead of him and cuts the string with scissors.
- Top Cat does the coin on a string trick during the opening credits; snatching the coin back from a doorman after he has tipped him.
- In the Warner Bros. cartoon short The Mouse that Jack Built, the mouse played by Jack Benny goes down to the cheese vault (counterpart to the money vault in the radio shows). He opens the first door by putting a coin on a string into a box, then pulling it up again. Since Jack Benny often played a cheapskate in his radio shows, this might have been to keep in character.
- A flashback on The Simpsons implies this helped Mr. Burns make his fortune.
- The Proud Family: Oscar Proud is cheap enough to do this with a charity donation during a Christmas special. Penny isn't impressed.
- Dastardly and Muttley in Their Flying Machines: In "Operation: Anvil," Dastardly relieves Muttley of his medal after he botches an operation to catch Yankee Doodle Pigeon. Muttley had a string tied to the medal, so as Dastardly walks off, Muttley yanks the medal back.
- The Goof Troop episode "Maximum Insecurity" had Leech use the coin-on-a-string trick to snag a free soda from a vending machine. PJ then runs into him and gets him mad by breaking the string and making him lose the coin it was tied to.