A 535D at 300km/h (186mph) http://www.youtube.com/watch?v=meMsemxQZlE&feature=related

hard way and longest way (probably more than 1 year) #day 1: buy a pickup #day 2 to day 300: take one year or more to make it go at these speeds, dealing with aerodynamics, mechanical parts, supercharging the motor etc. easy way and fast way (3 days) #day 1:buy a aerodynamic eficient disel car with a lot of power like a bmw 635d, remove the electronic speed limit (it's limited to 155mph), buy some B100 biodisel #day 2: drive to the desert #day 3: beat the speed limit