Last year, applied mathematician Jeffrey Aristoff and mechanical engineer Howard Stone, both of Princeton University, were at the gym waiting for a pickup game of basketball. To warm up, Stone started jumping rope. As the rope whizzed over the head of his colleague, Aristoff wondered, "Is it known how jump ropes bend in the wind?" A few literature searches later, he concluded that the answer was, "not really." Now, the two have solved the problem themselves.