about 1,000 to 1,140 horsepower (depending on fuel), about 3,200 pounds—continues to crush passengers in excess of 1g of linear acceleration until somewhere north of 100 mph, at which point the car's aerodynamic shape begins to exert significant downforce (660 pounds at 155 mph). The rate of acceleration levels off but it's still going upstairs like crazy (124 to 186 mph takes 7 seconds). This is telemetry as pornography.

Mr. Koenigsegg estimates the car's top speed would clock in around 273 mph—faster than the Bugatti Veyron Super Sport's record of 267.8 mph—if, that is, he could find some stretch of Mars upon which to test it. On the company's conveniently located airfield, the prudent visitor gets on the brakes after touching 186 mph (I hit 190). The braking event from that speed requires less than 7 seconds and is likewise vigorous. It feels like your pants are going to fall off.

The Agera R—$2.5 million or so