Cheating at Slot Machines
Cheating at slots is whole lot harder than it sounds and I wouldn't suggest trying it. First of all, cheating at a money game like a slot machine is essentially stealing money. If you're caught, you'll be treated like a thief, which is exactly how the casino will look at you.
With that out of the way, let me also mention that casinos and slot machine designers are always looking for ways to make their slot machines more secure. Probably from the beginning of slot machine history, cheating at slots has been a game of cat-and-mouse between gamblers and casino operators.
Famous Slots Cheats
Take Tommy Glenn Carmichael, considered by many to be the most successful slots cheat in casino gaming history. Mr. Carmichael developed the Monkey's Paw, which triggered a slot machine's payout mechanism. Slot designers eventually protected their machines from such a mechanical tool, and Carmichael eventually went to jail for his repeated attempts to cheat the casinos.
These days, Tommy Glenn Carmichael build anti-cheating devices. That's probably a lesson to other potential slots cheaters; if you really know the system that well, you can probably make more money working for the casino industry than against it.
Mini-Lights and Slot Machines
That being said, there are many methods used by slots cheats. One of the most successful in the modern electronic age of slots is the mini-light. This was a focused light which could be directed at the slot machine's sensors, confusing the machine about how many coins had been paid for a win. This worked for a while until casinos caught onto the scam. Now, all slot machines have protections against the tripping of their light sensors.
Counterfeiting and Slot Machines
More rudimentary means have been used to confuse slot machines. One of the most common of these is counterfeit coins, usually called slugging in the gambling industry. People who use counterfeit slugs are called sluggers.
This probably still works from time to time. But as casino technology has become more advanced, the defense against counterfeit money have also advanced.
Even less advanced methods have succeeded, though. One of these was the old coin-on-a-string method, which required dangling the coin inside a slot machine, then pulling the coin back out to be used again. Machine designers have developed catches to keep this technique from working anymore. In the future, coin scams will completely disappear, since coins and tokens will disappear from casino floors. It won't be too many years before casino gamblers use nothing but casino credit cards, which will be issued to players when they check in at the casino.
But the Slot Machine Didn't Pay
Another scam is to find a machine that just paid off a jackpot. In certain cases, a gambler will win a jackpot, collect their winnings and immediately leave that machine. When a slots scammer finds this situation, the cheat will set up camp at the machine, claim he or she has won, but that the machine never paid up.
In this case, the cheater creates a scene on the casino floor, demanding payment even when the machine shows it has already paid. This has happened for real before, but casino managers are going to be suspicious of a gambler claiming this has happened in their casino. This is one of the reasons that casinos have so many security cameras watching the casino floor, because they'll be able to track a gambler's progress through a casino.
What's Next For Slots Cheating?
Some new, inventive slot machine cheat will find a way to cheat that system, too, but the methods for scamming casinos are going to have become more advanced and elaborate as the industry evolves.