Current nanotechnology, involving man-made objects or machines less than 100 nm (nanometers) in size, is well into the development phase, and the first practical applications are already on the market. (See information on current sunscreens using nanotechnology, and the risks of using them. link) Research into nanotechnology has currently created only very simple machines: small gear sets, electric motors, and radio receivers, to name a few. Nano-sized machines have some inherent limitations, however.
I’ve read that physical factors like Brownian motion and friction create a very challenging environment for nano-machines, and are not easy for the average person to comprehend without additional information and a better understanding of such factors. So, what is the next step towards realizing the value of nanotechnology? For want of a better term at present (and I am confident that one exists) I will use the term “microtechnology”. By this I mean to indicate a larger scale of objects, perhaps up to 100 microns in size (1000 times larger than nano-objects).
I believe it just a matter of time before nanotechnology machines become more complex and larger, and achieve much more sophisticated functionality. I foresee radio-controlled microtechnology machines, less susceptible to the limitations of nano-size, but still small enough to be invisible to good optical microscopes, let alone the human eye, with many and more sophisticated functions than can be achieved at nano-scale.
Eventually we could see machines, some potentially with biological components, at all relative scales from nano-scale to that with which we are already familiar. There are undoubtedly many as-yet unexplored possibilities for machines working at the intermediate scales. I have yet to see information on work being done in these areas, but will be excited to see what can be (or has been) created.