Quite possibly the Ford Pinto....seemingly small rear impacts used to rupture the fuel tank which would then leak onto the hot exhaust system leading to many cars combusting in front of the owners eyes (and sometimes with them still inside).
McLearn F1! The designers at woking started with a Formular 1 car and changed the design until it became road legal.
Best classic car aston martin V8, which later became the DBS.
Best affordable performance car Caterham Super 7 few creature comforts but made up for by a 0-62 time of less than 4 secs!