Bugatti Veyron Super Sports --- the most horsepower, the fastest top speed and acceleration -- and -- most expensive .:. .:. image credit: http://www.worldsmostexpensivecar.com/bugatti-veyron-super-sport/
"The Bugatti Veyron EB 16.4 is a mid-engined grand touring car, designed and developed by the Volkswagen Group and manufactured in Molsheim, France by Bugatti Automobiles S.A.S. The Super Sport version of the Veyron is the fastest street-legal production car in the world, with a top speed of 431.072 km/h (267.856 mph)."