16. Porsche 916
Even if it looks like an ordinary, four-cylinder Porsche 914, the 916 is a totally different animal. This special model was a rolling experiment on how to put an engine from a fantastic 911 2.7 RS into a smaller, lighter body.
The results were amazing, but Porsche feared that nobody could tame this beast or buy it since it was so expensive. In the end, the company built just 11 examples, which most people consider the Holy Grail of the Porsche collector community.