We all carry an ideal car in our imagination. Its form becomes an aesthetic template that makes us want one vehicle and not another. Behavioural scientists believe our choices involve deep-rooted impulses that may reach back to our time in the womb. The process is not unlike the one we use to choose a mate, and Is often ruled by irrational fears and inexplicable longings. <p>Here are eight very different car shapes, and what they say about the drivers they appeal to.</p>