So, I just saw a newspaper article about a startup in India that has invented a device to make ink from vehicle smog The inventer noticed that the soot from diesel cars was turning his clothes black, and thought that he could clean the city's air by making that smog in to ink. He and his team at Graviky Labs then went about building a device that will capture particulates from vehicle exhaust. These are then processed to remove toxins such as heavy metals, and the recovered-and-cleaned carbon soot then turned in to ink for use by artists. They have partnered with Tiger Beer to market the invention & raise investment to get the inks to market - and smog removed from our cities' air. So far, they are showing spray cans and marker pens, and refill bottles for them. I hope that they will start making carbon-black ink for fountain pens. http://www.graviky.com/air-ink1.html http://www.air-ink.com The second website is hosted by Tiger Beer, so requires you to enter your country of residence & date of birth to prove that you are of legal drinking age.