Yes it is! I've been down the mmWave rabbit hole for the last 6 months, making sensors to put around the house to control automations for lights and so forth.

Yes it is! I've been down the mmWave rabbit hole for the last 6 months, making sensors to put around the house to control automations for lights and so forth. They're pretty great. For my use case the advantage over PIR is they do presence detection, so no more lights shutting off when you're sitting on the toilet. Pretty amazing you can pick up basic mmWave sensors for a few bucks on amazon, and mate them to an esp32 board which is another couple bucks. It's so much fun as a hobby!