- Veryron -
EDIT: Just last year it was the fastest car in the world, but I think someone made a car faster.
That's the Bugatti Veyron SS (Super Sport). The faster car was the SSC Ultimate Aero. The Veyron SS is the lighter, faster, version of the original. They lightened it by 200 or so pounds and increased it's horsepower by 200. I think they hit a max speed of like 430km/h and could theoretically go faster, but they didn't have enough road.