26. 1974-1977 Mazda Rotary Pickup
The Mazda Rotary Pickup was the first and only pickup truck to use Mazda’s unique “Wankel” rotary engine. Rotary engines are unique in the auto world. While most automobiles are piston-powered (and increasingly, battery-powered), Mazda’s rotating Wankel engine relies on a rotor that moves around the engine block in a sort of figure-eight. For its day-and-age, the Wankel engine offered a lot of power-to-weight ratio, although the engine has since fallen out of favor. If you’re looking for a unique part of combustion-engine history, the Mazda Rotary Pickup certainly fits the bill.