What if you could interact with advertising posters that you pass, or get more information from display boards in shops, libraries and other public places? Soon you could be able to, thanks to a revolutionary new interactive paper technology.

Swedish researchers are developing working prototypes of a digital paper that can communicate with computers.

The paper blends printed graphic codes and electronically conductive ink that is sensitive to pressure. This functional layer is sandwiched between a thick sheet of extra-strong cardboard and another sheet of paper printed with the billboard's design. The paper emits sound via the printed speakers when touched.

Research teams at the Mid Sweden University forestry industry research program Fiber Science, and Communication Network (FSCN) are working on the new paper products. They hope the technology will help integrate paper with the digital world.

"We combine paper with printed graphic codes and electronically conductive ink that is engineered to be sensitive to pressure. Then digital information is embedded in the paper, and when it is touched, the information comes out via printed speakers," said Mikael Gulliksson, project leader for media technology in the comprehensive research project.

Possible applications for the Paper Four technology include advertising displays, in-store promotions, tourism information displays and even product packaging.

"One interesting idea would be to use it on cigarette packaging, so instead of having a written message warning you of danger to your health, you would have a spoken one," said Mikael Gulliksson, project leader for media technology in the comprehensive research project. "There could be a whole range of applications," he said.

Pressing the button on an advert for a holiday destination, for example, would play a message about that place. It might give you a description of key attractions and invite you to interact with the message. The sound is streamed out the paper that the advert is printed on.

A video showing the paper technology can be be seen here .