Nano-scale devices have been around for a while now, filling functions such as chemical sensors of extraordinary sensitivity and selectivity, your computer's CPU, and the read/write head on the hard drive. There has also been a lot of progress on what people would recognize as nanomachines, too: motors, gears, switches, all on the nano-scale.
In most cases, however, they're still difficult to make, using the same sorts of high-purity, cleanroom processes as for computer CPUs. Yes, those are in mass production as evidenced by how there are computers in everything these days, right down to doorknobs, but it's still an intensive process requiring extreme purity and cleanroom procedures.
Until recently, that is: some nanoscale devices can now be made easily, even with something as crude as a tabletop vise. Plus, the crucial part, a stamp.
The stamp was made using the cleanroom process, and once complete it can stamp out multiple copies of the actual device outside of a cleanroom, which makes them much cheaper and faster to produce.
One thing that is particularly interesting to me as a chemical engineer is how simply changing the coating on the nanostructured surface (for example, a tiny diffraction grating) changes what chemicals it detects (or more specifically, what chemicals stick to it). Then, on shining a light on it, the presence of those stuck chemicals changes the reflection or diffraction pattern in a way that's proportional to the amount of chemical adsorbed. And, moving outside of my field of expertise, biological molecules can be very specific in what will stick together and what will not. There's a lot of work going on to make these sensors to detect specific enzymes or enzyme activity that are characteristic of a disease, antibodies, and even parasites.
Making these sensors faster and cheaper means that development of useful tests for hospitals, and maybe eventually your GP's office, will speed up dramatically.