Everyday Devices (image) University of Washington Share Print E-Mail Caption Everyday objects could be enabled with battery-free tags to communicate with each other. A couch could use ambient backscatter to let the user know where his keys were left. Credit University of Washington Usage Restrictions Photo credit required. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.