There is a new technology that uses the wifi, bluetooth, or other radio signals around us to provide power for small devices. It is called Freevolt. What could we do with this?
One idea is to marry it with an acid gas sensor in the Glowforge to alert us to the presence of hydrochloric acid, hydrogen cyanide, etc that might be generated from bad glues and other materials. Combine it with a graphene based supercapacitor for more power.