Over almost two decades, Tommy Glenn Carmichael stole millions of dollars from casinos by devising ways to rig slot machines. One of his inventions, known as the slider or monkey's paw, was a wire he would insert through the machine's payout chute to trip the microswitch, tricking the machine into releasing a jackpot. As slot machine technology improved, so did Carmichael's techniques. Using a camera battery and a small light bulb, he invented a light wand that could blind a slot machine's sensor and trick the machine into spitting out coins. According to The Los Angeles Times, Carmichael managed to rake in thousands of dollars a day rigging slot machines. In 2001, Carmichael was caught by an FBI investigation and served 326 days in prison and three years' probation. He was also banned from entering casinos.From the 1970s to the 1990s, the MIT Blackjack Team used card-counting techniques to beat casinos and earn millions. Composed of students and ex-students from MIT, Harvard, and other prominent schools, the group was one of the first blackjack groups to use organized, scientific tactics to beat casinos at their own game. The group's ringleader, Bill Kaplan, trained more than 100 blackjack players over the years and supposedly made $10 million for himself and investor at casinos around the world, according to Inc., which described his card-counting as frowned-upon but legal. Eventually, casinos caught wind of the elaborate scheme and began barring members of the team from gambling. Although some members continued to play into the 2000s, the team had mostly broken up by 1993. The team's exploits helped inspire the 2008 movie 21.In the early 1990s, Ron Harris was a software engineer writing anti-cheating software for the Nevada Gaming Control Board. But secretly, he was coding machines with a hidden software switch that paid out huge jackpots when players inserted coins in a certain sequence. According to CNN, Harris rigged 30 machines before getting accomplices to play the slots and walk away with hundreds of thousands of dollars. Harris was eventually caught when one of his accomplices was busted trying to rig a game of keno in Atlantic City. Harris pleaded guilty in 1996 to four counts of slot-cheating, according to the Las Vegas Sun, and was sentenced to seven years in prison. Louis Colavecchio, known as the Coin, was a renowned counterfeiter who used fabricated slot-machine coins to win thousands of dollars from Vegas casinos without betting a dime of real money. In 1997, he was convicted and sentenced to 27 months in federal prison for his manufacturing of the coins, according to CoinWeek. New Haven Register reported he had 750 pounds of coins in his car when he was arrested in Atlantic City. Colavecchio was arrested again at age 76 last year in Pawtucket, Rhode Island, for counterfeiting 2,400 fake $100 bills, according to the Providence Journal.John Kane managed to win more than $500,000 playing video poker by exploiting a software bug found in machines across the country. According to Wired, Kane inadvertently discovered a glitch in the Game King line of video poker machines that allowed players to replay hands with different base wagers. That meant Kane could sit at a machine for hours betting one cent at a time, and when he eventually scored a jackpot-winning hand, he could replay the hand with a maximum wager of $10, earning him a payout of $10,000 or more. Kane and his friend Andre Nestor, who took part in the scheme, were eventually arrested, but they both walked free after federal prosecutors failed to justify charges of hacking and conspiracy. All these guys did is simply push a sequence of buttons that they were legally entitled to push, Kane's attorney said.With cameras everywhere in casinos, William John Brennan still found a way to disappear. Brennan was a former sports book cashier at the now-demolished Stardust hotel on the Las Vegas Strip. In 1992, Brennan walked out the door of the casino with $500,000 worth of cash and chips in a bag and was never seen again, according to the Las Vegas Sun. News 3 Las Vegas reported he was assigned to count money at the sportsbook following a Monday Night Football broadcast, wrapped it up for deposit, and disappeared. Perhaps most puzzling, according to the reports, was that no cameras picked up his exit. A warrant was issued for his arrest, but the case remains unresolved almost 30 years later.After a move to Las Vegas left Richard Marcus homeless, he found a job as a blackjack and baccarat dealer. As he learned the ins and outs of the games, he discovered ways to cheat the system, according to his own website. One of his most successful scams was past posting, or late betting, in which he'd wager low amounts, wait to see if he'd won, and then discreetly swap out low-denomination chips for higher-value ones to earn huge payouts. His sleight of hand could turn a $300 win into a $10,000 one in seconds. According to CNET, he was eventually caught by law enforcement, but was never convicted, and managed to swindle more than $5 million from casinos. Now, Marcus is a casino protection consultant and sells books about his escapades.In 2016, Bellagio craps dealer Mark William Branco and two accomplices, Jeffrey Martin and Anthony Grant Granito, were arrested and charged with at least four years in Nevada State Prison for scamming the casino out of more than $1 million. According to The Las Vegas Sun, the group would go to craps tables that Branco and another dealer were manning and place phantom hop bets, or high-value bets that a specific combination of numbers on the dice would be rolled. The Sun reported that one of the two players would mumble something that sounded like a hop bet and one of the dealers would pay out as if they had correctly wagered on whatever fell. The group tried their trick 76 times over two years, officials testified. According to the Las Vegas Review-Journal, casino personnel caught on when they realized the group's luck defied 452 billion-to-1 odds. The group was ordered to pay hundreds of thousands of dollars in restitution by the Clark County District Court Judge, according to the Reno Gazette Journal. Branco is serving four to ten years in prison. He is also now No. 36 in the Nevada Gaming Commission's black book, which makes it a felony if he ever enters a casino. From 2009 to 2013, sports book operator Cantor Gaming was caught in a massive illegal gambling and money laundering scandal. According to Reuters, the company's former director of risk management Michael Colbert and his staff knowingly took large illegal deposits from out of state and processed the illegal winnings. The staff also allowed two illegal bookmakers to launder money through the company. The Las Vegas Sun reported more than $2.8 million was seized in 2012 in an initial probe, and 25 arrests were made, including Colbert. Cantor Gaming, now CG Technology, agreed to pay $22.5 million to resolve the issues in 2016. Colbert pleaded guilty in 2013 and faced up to five years in prison, but his charges were dropped with the settlement, according to Casino.org.