World’s strongest robot muscles made from everyday fishing line

For a thousandth the cost of his carbon nanotube muscles, Baughman and his team have constructed a fishing line muscle capable of lifting objects 100 times heavier than natural muscle of the same size. They’re also more powerful, putting out the equivalent of seven horsepower per kilogram, more powerful than a car.
The secret of these crazy-strong muscles is a combination of coiling and heat. Think of a model airplane with a rubber band-powered propeller. The more you twist that rubber band, the more energy it has stored up inside it. By then heating the already-coiled fishing line, Baughman’s team was able to contract the "muscle" further, powering the muscle without releasing all that built-up tension. Just one fishing line, ten times the width of the hair on your head, can tirelessly lift up to 16 pounds.
What’s more, by precisely controlling the heat acting upon the coils of fishing line, researchers were able to reliably control the muscles. The wide variety of fishing line strengths available could mean that, in the not-so-distant future, artificial limbs and robots alike could have tailor-made arms capable of superhuman feats of strength.