University of Toronto researchers have built "nano-propellers" that are 1/500th the width of a human hair. Hydrogen peroxide acts as the fuel, causing the gold and nickel "blades" to release gas bubbles that provide enough thrust for them to spin. From BBC News:
But researchers admit that if nano-machines are to have a future, ways must be found of getting different parts to interact as a functional whole.
"Rotational motion is at the heart of many conventional machines, such as rotary engines, screws and clocks," said Professor (Geoffrey) Ozin. "However, these machines clearly need more than just a rotor."
