We already know that it's possible to map your home's WiFi signal in 2D, but that doesn't help if you're holding your phone above your head to get connected. Step forward YouTuber CNLohr, who appears to have developed a reasonably low-tech way to analyze the WiFi strength of any 3D space. Using just a WiFi module and a CNC mill, he was able to detect the variability of the signal in an area and then create the funky visualization you see before you.