I’ve long thought of traffic as one of the great unifiers of humanity. We all have different loves, desires, hobbies. But the one thing uniformly detested is wasting time unnecessarily, staring at brake lights.

Just how damaging is it? A new report from the Texas A&M Transportation Institute says 5.5 billion person hours were wasted sitting in traffic 2011 (the last full year that researchers have measured). That translates to lost productivity of $121 billion.

If you’re a city planner, that’s a big problem. But if you’re an engineer or traffic innovator, that’s also a huge opportunity. Traffic is one of modern society’s greatest inefficiencies, and considering how wasteful those hours spent slowly idling become, there’s a lot of money waiting