Two-way molecular communication, analogous to the chemical signalling used by plants and animals to control their bodies and communicate with other organisms, has been demonstrated between inorganic nanoparticles by researchers in Spain. The research is a step towards producing co-operative nanoparticles, which could be useful in multiple areas of science and medicine. From the invention of the telegraph to Web 2.0, humans have communicated using electromagnetic waves. This can be problematic at the nanoscale, as the technology needed cannot be miniaturised below the wavelength and the power requirements are prohibitive. Nature cracked this problem billions of years ago: organisms can send messages to other parts of their bodies using hormones and other chemical messengers. Humans have produced simple synthetic versions of this kind of molecular logic for controlled drug release and other applications, but the sophisticated multi-way chemical communication seen in nature has not b...