Stanford University researchers led by postdoc Nariman Farsad have built a machine that sends text messages using common household chemicals. The chemical communication system relies on a binary code to relay messages, but instead of zeros and ones, it sends pulses of acid (vinegar) or base (glass cleaner). The researchers type their desired message in a small computer. The computer then sends a signal to a machine that pumps out the corresponding chemicals, which are sent through plastic tubes to a small container with a pH sensor. Changes in pH are then relayed to a computer that deciphers the encoded message. Farsad chose these specific chemicals because they are easy to obtain and they cancel each other out at the receiving end of the system. The researchers are currently looking into how chemical communication could advance nanotechnology. Cost-effective nanotechnology already exists that may someday go inside the human body. But these devices are so small that, in order to communicate, they have to be wired together or else depend on high-frequency signals, which could potentially cause organ damage. These signals also tend to only travel short distances and powering them has yet to be figured out. As an alternative, chemical-based data exchange could be self-powered, traveling throughout the body harmlessly - and undetectable by outside devices.