While most of us can only dream of owning the fastest car in the world, some will do whatever it takes to possess such speed and power.So, how fast are the fastest cars in the world? Here is the 10 fastest cars available on the market measures by top speed.1.SSC Ultimate Aero: 257 mph+, 0-60 in 2.7 secs. Twin-Turbo V8 Engine with 1183 hp, base price is $654,400. Tested in March 2007 by Guinness world records, The SSC Ultimate Aero takes the lead as the fastest car in the world beating Bugatti Veyron