From Mr. Stone’s article…
Xerox on Tuesday announced a new silver ink (among other things) that it's calling, and apparently is, a breakthrough in printable electronics, a leading edge concept that's generated a lot of discussion but few actual products to date, largely because of the issues that Xerox's new technology addresses.
In concept, printable electronics is just what it sounds like: using a printer, basically an ink jet, to print electronic circuits. If you can do that reliably, you can print electronic devices for far less than current methods cost. You can also print the devices on a variety of new materials.
The possibilities range from printing on flexible plastic (opening the door to displays you can roll up and put your briefcase), to paper and cardboard (for packaging that can give audio and video instructions for assembling a product, actively remind you to take your medicine, or confirm whether you already took it), to fabric (which will allow wearable electronics -- a T-shirt with a display, say, replacing a printed slogan for marketing or for showing support for a political candidate.)