1 Ltd has developed a new type of actuator called Helimorph, that uses PZT piezoelectric materials that have been layered into a helix, separated with conducting electrodes. When voltage is applied the free end moves parallel to the axis of the major helix, resulting in large (several millimeters) of displacement, whereas conventional piezoelectric materials move on the order of microns.
Read more on the 1 Ltd web site.