The Bugatti Veyron 16.4(also known as the EB 16/4 Veyron) is the most powerful car in the world (as of 2005).
The car is built by Volkswagen AG subsidiary Bugatti Automobiles SAS at its factory in Molsheim, France, and is sold under the Bugatti brand. The name of this car is taken from the name of a racer from France, Pierre Veyron who won the 24 hours of Le Mans in 1939 as a racer representing the Bugatti company.
According to Top Gear, this car was made by the company for the experiment that a car speed of 100 km/hour can be reached in under 3 seconds. It is made on a limited basis and is not intended for commercial use, so you should not be surprised if the insurance company does not dare to guarantee it.
