5. Cadillac Sixteen

Debut: North American International Auto Show
Year: 2003
Complex Says: Three years after the Imaj, Caddy took another go at mocking up a world-class luxury sedan, this time taking a cue from the V-16s of the '30s. Despite its cutting-edge styling, the Sixteen derived its name from the monstrous 16-cylinder engine crammed beneath its butterfly-winged hood. An engine of that size may sound a little intimidating, and portly, but using an engine-management system, the Sixteen would only use as many cylinders as needed. If Caddy wanted a wheel up on the competition, we think this would have done the trick.