After two and a half years of work, researchers at the Flexible Electronics department of the Centre Microélectronique de Provence – part of the French engineering school IMT Atlantique – have incorporated a battery into a contact lens and used it to power an LED for hours at a time. The battery is a milestone on their quest to develop an oculometer – a device to track eye movement – that can be mounted on a contact lens. To make the battery and the connected circuits more transparent, the researchers will now begin using graphene: highly durable sheets of carbon one atom thick. The overall technology's virtual-reality applications are, of course, manifold. Such lenses could be used for anything from driving to surgery. They arguably bring us closer to cyborg technology, where man and machine interact directly. For now, though, the researchers have struck a deal with LCS, the French manufacturer of contact lenses, and will be working with the Institut de la Vision to develop aid devices for the vision-impaired. Microsoft, which has already developed a contact lens to measure glycaemia, might invest $2 million in the project, and the Defense Advanced Research Projects Agency (Darpa), the research arm of the U.S. Department of Defense, has also shown interest.