The Toyota Prius c made an impression at the Detroit Auto Show this year. The c was the only car that doesn't need to be plugged in to top 50 mpg. One key feature enabling that kind of fuel efficiency is the Eco mode that allows drivers to travel about one mile, at speeds up to 25 mph, on electricity alone. The Prius c three-door hatchback will start under $19,000.

Read more about the Prius c here.