6. GM Runabout
The 1964 GM concept they named the Runabout may be forgotten but it was interesting for several reasons. First, it was quite different from the luxury, sports, and exotic cars that were common on the concept car circuit. In fact, it was the concept of an urban, affordable, small and modest runabout GM designed for shopping and short daily commutes.
But most importantly, it came with several interesting solutions like a big rear hatch to accommodate a shopping cart. Nowadays, most car fans would love to see a modern version of this concept car make a return.