The development of mobile un-tethered microscale robots could revolutionize the future of medicine, since they can be conceived to move in micro-structured liquid environments, such as in inaccessible districts of the human body for performing in vivo diagnosis and therapy. However, power supply and actuation are still open issues in microrobotics, because of the lack of power sources and actuators at these scales. Considering the amazing levels of functionality exhibited by microorganisms, bioinspiration is an attractive approach to address the development of innovative solutions. The demonstration of efficient methods for building, powering and steering microscale robots are thus the first crucial steps towards such advanced systems.