Tom Schelling up at U. of Maryland gets the Nobel prize this year. He really deserves it. I first came to know about his work while I was a graduate student at George Mason University, taking a course in Industrial Organization taught by Tyler Cowen. And one of the required texts of that course was Tom's Strategy of Conflict. Incidentally, Tom was one of Tyler's thesis advisers before Tom left Harvard. Read Tyler's posts on his mentor's contributions to economics here.
On an overview of Tom's work, read his interview here. Still curious about how important Tom's work is? Take a look at my mentor Dick Wagner's syllabus for his graduate macroeconomics course last fall. There were only 3 required texts for the course and one of them is Tom's Micromotives and Macrobehavior!