The new system, dubbed BrainNet, was tested by wiring three test subjects up to machines that let them send messages to each other using just their brainwaves.

Our brains have been communicating with each other for as long as they've existed. One brain can send signals to the fingers to write a letter, for example, which can then be posted so another brain can absorb the message through the eyes. But with the advent of experimental technology enabling direct brain-to-brain communication, things are starting to enter the realm of science fiction.