13. Chevrolet Astro II
Chevrolet’s 1968 Astro II was a sleek, mid-engine sports car concept that promised an era of accessible American exotics. With its striking proportions and forward-thinking layout, it teased enthusiasts with the idea of a mid-engine Corvette.
However, Chevy never took the project beyond the prototype, leaving this vision dormant for decades until the dream finally became reality much later.
Read more at GM Heritage Center