In 1984, ice cream truck driver Michael Larson set a record by winning $110,237 (a combined total of cash and non-cash prizes) in one appearance on the game show Press Your Luck—and he did it by gaming the system. He had noticed that the Press Your Luck board did not rely on luck at all, but was actually running in five predictable patterns, which he memorized over the course of six weeks (with the help of a VCR). By the time the show's taping was completed, everyone from the host to the contestants were mystified by Larson's amazing ability to avoid the Whammy (the squares on the board which would end the player's turn) and consistently win prizes.
Larson's original appearance was aired as two episodes due to the length of his winning streak. Producers initially tried to avoid paying him, since his pattern-memorization might be considered cheating. Eventually, the producers relented, after determining that the official game rules did not prevent a player from reverse-engineering the game patterns. Indeed, producers later revealed in a documentary that they knew there was a weakness to the game (only having five board patterns without any randomness), but the weakness was ignored until Larson's famous performance. Furthermore, in order to get spins on the board, Larson had to answer trivia questions, which relied on his trivia skills.
The original Larson shows were aired in June of 1984, then were not seen again in their entirety for almost two decades. But they are on YouTube, along with a documentary about Larson's experience (the documentary also shows the great majority of the show video, along with extensive followup from everyone involved).
GAMING THE GAME SHOW
Watch in amazement as the humble Larson goes on a winning streak. Pay particular attention to his focus, and how he often appears to celebrate a victory at the moment he strikes the button, rather than the moment the prize is explained to him—indicating that he knows the pattern, and is happy when he successfully hits the button at the right time.
Below, the first episode ends with the player on the left holding his head in his hands.
Wikipedia has an extensive narrative about what happened to Larson after his win. The short version is that he lost part of his money in a bizarre scheme involving $1 bills and a radio game show, and he lost the remainder when his house was burgled (he reportedly had $40,000 in $1 bills in the house). Two years after winning, he was working as an assistant manager at Walmart.
Larson eventually became involved with an illegal lottery scheme and lived his remaining years on the run from the law, eventually dying from throat cancer in Apopka, Florida in 1999 at the age of 49. It's a sad story—and one that has been written about more extensively at Snopes. Larson's story was also discussed on an episode of This American Life.