Ninety-three percent of Americans drive to work alone. So why use a car that’s big enough for four? A new vehicle that’s half-motorcycle and half-car is designed to replace sedans and SUVs on morning commutes and help save money and emissions in the process: The Elio costs $6,800 and gets 84 miles to the gallon. It’s possible to drive 672 miles on a single tank of gas. That’s the distance from New York City to Detroit.