When one speaks of microscopes one usually imagines devices which produce spatially resolved images. So it is most intriguing when a novel application of microscopic techniques permits discoveries not by forming images but by allowing very precise measurements to be made on very small objects. The blind showing the way to the sighted! A recent paper in Nature is a good example of what I speak. It deals with biological motors, which, as cell biologists are learning, are involved in the movement of cells and the movements of organelles within cells. There are a number of different biological motors, but all are molecules which change shape, as they convert the chemical energy derived from the hydrolysis of high energy molecules such as ATP, into mechanical work. As the motor molecules undergo this conformational change and then return to their original state they take a step away from their starting point, dragging along the structures to which they are attached.