Next year, congestion pricing is coming to New York City. And maybe, just maybe, the toll for motor vehicles entering the lower half of Manhattan should be set at $100. That number comes from Charles Komanoff, an environmental activist, a transit analyst, and a local political fixture. It represents neither the amount that would maximize revenue nor the amount that would minimize traffic. Rather, it is an estimate of how much it really costs for a single vehicle to take a trip into the congestion zone—in economists’ terminology, the unpriced externality associated with driving into one of the most financially productive and eternally gridlocked places on Earth. To be clear, Komanoff does not actually think that the state should charge each car, pickup, and box truck $100. He doesn’t think the toll should be anywhere near that amount. “At heart, I’m very much a radical,” he told me as we sat outside a stylish coffee shop in SoHo, to which Komanoff had brought his own coffee in a thermos. He has been detained numerous times …