Interesting... I knew the Harris story but not much about Volk. A couple of the commentors said only 30% of the chips were gaffed, so somewhere between 30-50%. They were smart enough not to modify all of the machines (and only max bet Royals) so this means they only brought in probably 1% at most. Seems pretty stupid and they didn't get away with it for very long. Mickey, do you think there are still gaffed VP machines around?

From LVA:

On October 1, 1990, Larry Volk, a 49-year-old former computer programmer for the American Coin Company, was gunned down in his backyard. Volk, the quintessential "man who knew too much," was dead long before paramedics reached the scene.
At the behest of American Coin’s owners, Volk gaffed the computer chips on 500 or more of the company’s video poker and video keno machines. Volk's rigged programs prevented royal flushes from being hit when players bet the maximum number of coins, so the slot route operator wouldn't have to pay off the big jackpots. The cheating "resulted in $17 million in fraud," according to the Las Vegas Review-Journal, and ran undiscovered from 1986 until 1989, with upwards of 500 of the company's 1,000 video poker machines affected.
The Nevada Gaming Control Board was already running a sting on American Coin for illegal interstate sales of slot machines when the gaffed chips were brought to its attention in June 1989. After chips were pulled from American Coin machines in a half-dozen Las Vegas bars, regulators discovered that they didn’t match the "master" chips on file with the state. Still, they probably couldn’t have nailed American Coin, but then Volk rolled on his employers, Rudolph LaVecchia and his son Rudy, and paid the ultimate price.
In a 1999 interview, an anonymous Metro detective called the American Coin case "a frustrating situation. We thought the LaVeccchias were involved, but we could never build a case against them."
The LaVecchias weren’t completely out of the woods. Rudolph and Rudy neglected to pay the million-dollar fine imposed by the Gaming Control Board over the scandal. On Jan. 15, 2001, a District Court judge handed down a $1.24 million judgment against the twosome, effective closing the book on the American Coin case.
No casinos were involved, as American Coin serviced only Las Vegas bars.
As for it happening today, we'd say that the Enforcement Division of the Gaming Control Board is 30-plus years more experienced than it was in 1989, with more agents providing more oversight. Also, American Coin seems to have been an anomaly, at least as far as history is concerned; why risk a good business, huge fines, and jail time when running gambling games is so profitable to begin with? But in gambling, as in life, anything can, and does, happen.