Imagine, smart dust all over the place - in your kitchen, under the bed, on the coffee table, in your computer... all of it communicating with other smart dust so that it can find out exactly what you are doing on your computer... and after further development, observe, camera-like, all of your activities.

Think of it. No need for cellphones. No way to have any privacy. Simply talk to the dust, and the appropriat answer from the appropriate person will come to you, audio and video... through the dust in your ears, and the dust on your eyeballs, and all the linking computerized smart dust worldwide.