Number produced: 17 Price at auction: $7.3 million It's hard to image a time in automotive history when some car engines only produced 10 horsepower, but at the dawn of the 20th century, it was enough to get the job done. Two companies, Rolls and Royce, teamed up to build 17 of these early automobiles. A humble 1.8-liter twin-cylinder engine powered the cars. It follows the early tradition of looking like a horse-drawn carriage with a steering wheel -- and no place for a horse. It has big, brass headlamps, wooden spoke wheels and a horn that looks like a musical instrument. The car sold at auction for $7.3 million in 2004 and is the oldest known Rolls Royce in existence. Its chassis (number 20154) was updated in the 1930s but later restored to its original specification in the 1950s. It had been squirreled away in a farm building, perhaps to hide it from a foreign enemy, as was the case with many pre-World War II vehicles. The 10 hp was a development of Henry Royce's first car, the Royce 10, of which he produced three prototypes in 1903. This was itself based on a second-hand Decauville owned by Royce which he correctly believed he could improve. In particular, Royce succeeded in making his car significantly quieter than existing cars. Unlike the Royce 10 which had a flat topped radiator, the Rolls-Royce 10 hp featured one with a triangular top which would appear on all subsequent cars. The engine is a water-cooled twin-cylinder of 1800 cc enlarged to 1995 cc on later cars, with overhead inlet and side exhaust valves, and based on the original Royce engine but with an improved crankshaft. The power output was 12 hp (9 kW) at 1000 rpm. The car has a top speed of 39 mph (63 km/h). There is a transmission brake fitted behind the gearbox operated by foot pedal and internal expanding drum brakes on the back axle operated by the handbrake lever. Springing is by semi-elliptic leaf springs on both front and rear axles. It is a small car with a wheelbase of 75 in (1,905 mm) and a track of 48 in (1,219 mm). While 10 horsepower may not be a lot, it doesn't in any way diminish this Rolls Royce's place in history.