Mercedes 300 SL Alloy Gullwing
This Mercedes was arguably the first supercar in the world. It transcended the limits of the sports car class and went beyond design, power, and technology. Using space frame chassis, a fuel-injected straight-six engine, a host of components, and race-proven parts, Mercedes created a masterpiece with unusual opening doors and fantastic performance (via Hemmings).
A car like this one belongs in museums or even art galleries. However, one example spent days and years in a suburban garage in Santa Monica, under a pile of junk. The car was a graduation present and was purchased second-hand in 1971. It is one of only 29 made with an alloy body and semi-racing components. The owner drove it for a few years and parked it in the id-’70s. It was discovered 40 years later.