A superlative on four wheels, the Bugatti Veyron 16.4 is not only the world's fastest production car but also the most expensive: $1.25 million before taxes and richly deserved gas-guzzler penalties. Also, the most powerful: Its 8.0-liter 16-cylinder quad-turbo engine produces about 1,000 horsepower and churns it through a high-tech all-wheel-drive system and gob-smacking foot-wide tires. Also, the quickest: The Veyron accelerates to 60 mph in 2.1 seconds, faster than a Formula 1 car, but then it's just getting started. In 20 seconds — about the time it takes a fast reader to get through this paragraph — it reaches...