Nanotechnology smart dust. Computer artwork of sycamore-leaf-like nanomachines being dropped from a flying machine (upper left), demonstrating the concept of 'Smart Dust'. This aims to reduce the size of mechanical and wireless communication technologies to create machines the size of dust motes that can communicate with each other and send signals back to a base station. Motes that are 5 millimetres across have been built. Future uses of smaller motes, and swarms of motes, could include meteorological, geophysical and biological research sensors. They could also be used for surveillance, and even to create a distributed internet accessible anywhere.