I’ve gambled and won regularly (basketball, football), broke even (scratch off tickets) and gone from way up to busted (casino). I’m no high roller, but I’ve learned that to win big, you have to wager an amount that is uncomfortable to most people. Interestingly, being uncomfortable gives you a rush when you win AND lose, and a strange, incomplete feeling when you stop. “21,” the 2008 story of MIT kids that break the Las Vegas blackjack tables, is quite a thrill ride. But even though the inventive plot ties up all the loose ends, it’s still strangely unsatisfying. Ironic, huh?