In a market where SUVs ruled the road, the first-generation 2001 Toyota Prius hybrid introduced to the U.S. was all but ignored by the car-buying public. Small in stature and with looks that fell short of praise, the Prius faltered until the second-generation model in 2004. Today, the four-door Prius dominates the hybrid market for Toyota, leaving other manufacturers to play catch-up. With ratings of 48 mpg city, 45 mpg highway and 46 mpg combined, it's easy to see why the Prius dominates the hybrid market.