Sensory and motor homunculi

This is fascinating and bizarre. Below are pictures of what the human body would look like if each part was proportioned according to the area of the brain concerned with that part's motor control and sensory perception, respectively. In other words, our brains devote considerably larger areas to the sensory perception and motor control of the hands, say, than a random patch of skin on the back. Note how the motor homunculus is almost entirely hand and mouth - makes sense. (From the London Natural History Museum.)