Show Fuel Cost on Car Dashboards

Mandate simple mile-per-gallon and fuel cost per trip readout on dashboard instruments, integrated into all vehicles. Fuel usage and cost information would instantly tell us the cost of what we're doing ... and help us lessen the expense. We buy and operate vehicles as if we were racing, making driving the most expensive, wasteful way to travel. If the cost were continually in our faces, we'd soon begin driving more conservatively.