News Researchers print passive plastic Wi-Fi-connected sensors

A neat idea: they're modifying the response of an antenna by connecting or disconnecting a load using a mechanical switch (think the inside of a microswitch). These are relatively complex and bulky mechanical structures with lots of moving parts made of different materials. By the time you want to commercialise it, it'd probably work out cheaper to use a monolithic IC in place (stick the antenna on a die with a photoelectric cell, and use modulated light through a window to log the gear-teeth rather than a mechanical switch). Great if you're already using SLM to make the thing though.