Personally not a big fan (har) of their approach as so few ‘gpu’ spec server chassis really to plenums and decent fans very well. Most of the air typically finds another way out of the chassis.

It’s a fairly simple project, too: just hook an Arduino Uno up to a motion sensor and an electronic switch called a relay, then plug in your fan, and you’re good to go.

He hooked up a TMP421-based temperature module along with a TEMT6000 ambient light sensor to his Arduino, ... I too am thinking server room monitoring might be a secondary purpose for this device ...

The traffic light server monitoring system uses an Arduino microcontroller to interface with the Xymon server monitoring software. Xymon is an open-source tool that provides real-time monitoring ...

The researchers used an Arduino Uno board, an Adafruit LCD, a desk fan and a household spray bottle to transmit a short message across a tabletop, via molecular diffusion.