sciencehabit writes: Here's a twist: Scientists have designed a flexible, yarnlike artificial muscle that can also pack a punch. It can contract in 25 milliseconds—a fraction of the time it takes to blink an eye—and can generate power 85 times as great as a similarly sized human muscle. The new muscles are made of carbon nanotubes filled with paraffin wax that can twist or stretch in response to heat or electricity. When the temperature rises, the wax melts and forces the nanotubes to contract. Such artificial muscles, the researchers say, could power smart materials, sensors, robots, and even devices inside the human body.