Street Fighter

“Gridlock Sam” Schwartz is an icon in New York’s century-long war with traffic. Can his final campaign reshape the city’s transportation future?

Drone’s Day Scenarios

An invasion of unmanned aerial vehicles—drones to you—is on its way, but these flying robots are here to help, not enslave the human race. (At least, that’s what they say at Penn’s pioneering GRASP Lab, where some of the most sophisticated ones are being created.)