the image of spinning motors of no more than a hair's width graced the columns of newspapers in the late '80s. But what exactly would you do with a motor that is 70 microns (a micron is a millionth of a metre) wide? The rotating elements on these tiny motors produced a few trillionth of newton-meter of torque, probably enough to get a flagella to its destination, but not much else.

Now, nearly a decade after their development, few intrepid researchers have found compelling applications for miniature motors and microscopic machinery. These mite-size actuators, may prove ideal for manipulating something as light as light. Vanishing small machines can move tiny mirrors, lenses and other elements so that photons reflect, transmit or diffract. Engineers are calling this nascent field micro optio mechanical systems or moms ( Scientific American , Vol 275, No 1).

The us -based semi-conductor manufacturer, Texas Instruments, has perhaps best highlighted this integration of optics with electronics. The company has begun markets for an electronic display whose picture elements or pixels, are guided by micromechanical motors. The display contains 500,000 aluminum mirrors, each of which measures 16 microns on a side. The mirrors tilt into an