The researchers have used the pen to create a flexible LED display on paper, conductive text and three-dimensional radio-frequency antennas. They now plan to expand the palette of inks to enable pen-on-paper writing of other electronic and ionically conductive materials. While the pen is likely to prove attractive to electrical engineers and hobbyists, the researchers have also highlighted the potential of the device for creating art. Using the pen to sketch a copy of the painting “Sae-Han-Do” by Jung Hee Kim, which portrays a house, trees and Chinese text, the researchers used the ink as wiring for an LED mounted on the roof of the house that was powered by a five-volt battery connected to the edge of the painting. (via Silver pen allows electrical circuits to be handwritten on paper and other surfaces)