11. Porsche 911
At the other end of the spectrum we have the Porsche 911. It’s a common truism that the 911 is a “constant evolution” over nearly 50 years, and Porsche has milked this for all its worth – the first version of the 997 GT3, for example, used a modified version of the ancient air-cooled engine block, a component that has been paid off long ago. Add in Porsche’s often exorbitant price for options (charging hundreds of dollars for minutiae like colored wheel crests on the center caps) and people’s willingness to pay money for a prestigious status symbol and you’ve got a perpetual cash cow.