I first tried to do something like this about 10 years ago. I wanted to put a microcontroller in every switch patress and network them across the mains using a

I first tried to do something like this about 10 years ago. I wanted to put a microcontroller in every switch patress and network them across the mains using a TDA5051A modem. Unfortunately the size of the various components (including all the transformers and other passives) was too great for me to retrofit to exisitng hardware. I've come back to this recently, as I can now use a ZigBee module for comms, and by going surface mount I can get the required components in a very compact space. Never tried to do voice recognition in a socket, but that's a very interesting idea - have microphones in every patress and network them to create an array.