I made a 3D printed, Arduino-powered desk fan based around a 120mm Corsair QL120 ARGB fan after seeing Noctua’s desk fan. I wanted something similar but with RGB. It is based around CorsairLightingProtocol so it syncs with OpenRGB but also has a knob to adjust fan speed and LED brightness directly. I made a video showing it off but if you prefer to read about it, I have project documentation and files (code, assembly instructions, and 3D models) on GitLab here:

https://gitlab.com/CalcProgrammer1/OpenRGBDeskFan

The 3D models are also on Thingiverse:

https://www.thingiverse.com/thing:6655697