" And there were other neural implants being developed back then, including retinal implants, chips that enable a stroke patient to control his computer from his brain, an artificial hippocampus for boosting short-term memory, and many others. If you apply the approximately 30 million–fold increase in capability and over 100,000-fold shrinking in size that has occurred in the past quarter century, we now have much more capable devices that are the size of blood cells. Reader: Still, it’s hard to imagine building something the size of a blood cell that can perform a useful function. Terry2034: Actually, there was a first generation of blood cell–size devices back in your day. One scientist cured type 1 diabetes in rats with a blood cell–size device. It was an excellent example of nanotechnology from "

― Ray Kurzweil , Transcend: Nine Steps to Living Well Forever