A few years ago Ben Mezrich wrote a book called Bringing Down the House which was, surprisingly, not about Queen Latifah. He detailed the exploits of a team of MIT students who flew to Las Vegas on the weekends and used a system of card counting and small betting that allowed them to signal each other and place larger bets once they knew the remaining cards in a six-deck shoe were disproportionately high (10, J, Q, K, A). It doesn't sound like a big deal, and statistically increases their odds by a few percentage points, but it adds up in the long run. As it so happens with all rags-to-riches, rise-and-fall stories, their plan succeeded until they got greedy, and the casinos figured out what they were doing.
His new book, Busting Vegas, is more of the same. A new batch of MIT students are winning without counting cards. Instead they use 3 techniques designed to capitalize on the exact placement of a particular high card. (For 2 such techniques, they pick a dealer with small hands, clandestinely look at the bottom card after the shuffle, and cut the deck so they know exactly where that card will end up in play.)
Mathematically, the advantage to the player using one of these methods shoots up significantly, by at least 30 percent. And with increased reward comes increased risk: the casinos could not figure out what these students were doing, but they still initiated a shakedown or worse whenever possible.
The book doesn't explore it enough, but the truth is that the casinos do their own kind of math. As the author describes the actions of these young players playing under archetypal aliases (the drunken dentist at a conference, the Eurotrash pop star, the Russian arms dealer), it's apparent that their sudden and consistent success breaks all known patterns of blackjack winning, and therefore merits the wrong kind of attention. Also, these MIT students displayed an incomprehensible arrogance in believing that they could not be caught despite numerous incidents to the contrary. I left the book feeling neither compassion for the players nor antipathy for the casinos.