Don’t wire a circuit—doodle it. To connect batteries to devices such as resistors and LEDs, a newly developed ballpoint pen uses silver-based ink that conducts electricity through lines drawn over paper, wood, plastic and even some textiles. Jennifer Lewis, the materials scientist who led the pen’s design at the University of Illinois, says she is now looking for business partners and hopes to have products that integrate the pen and ink on the market within a few months. Check out video of the ink below!
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.