A group of college students used its math skills to win millions and life in the fast lane seemed like a sure bet. Slip back to the '80s and '90s, when a group of overachieving M.I.T. students morphed into high-rolling, big-stakes gamblers. Backed by anonymous investors, they checked into hotels under assumed names and, pretending not to know each other, communicated with secret gestures and code words inside the casinos. Betting $50,000 a hand, the students racked up millions in winnings before their ingenious scam folded.