A cool technology has been in the news recently — ambient backscatter. Basically, that’s all the excess TV and cellular signals that are already bouncing around in the air. A group of engineers at the University of Washington has harnessed this energy to power devices and allow them to communicate with each other. That way, the devices need no batteries, so are essentially maintenance-free.
The example they show includes monetary transactions between cards, seen below. In the video, they suggest how your couch might be able to text you that you dropped your keys there! Sounds a little out there, but one can only imagine where this technology could lead.