Gullwing doors are one of the most eye catching automotive design elements, but all too often they're either from tacky aftermarket kits or were included by the designer for the sole purpose of looking flashy. In the 300SL, the car for which they were invented, they served a very valuable purpose though; they allowed for additional reinforcement of the chassis near the bottom of the car that helped the 300SL to go on to be a world-beating supercar and race car.