@AWI
This is how it looks like at the moment.
Still taped together as everything is beta stage. ;)

https://youtu.be/_hbFNwnpov0

my bathwater sensor

waterproof Ds182b & TM1637Display

use it with domoticz & edomoticz Homebridge plugin so Siri can tell me if my bath temperature is hot enough or not :)

9v at the moment because no regulators at hand...
case is custom lasercut at snijlab.nl

@BulldogLowell said:

Kelvin or Celcius?

Nice project, I think I might use it for my pool...

where did you get the laser cut acrylic?
Celsius :)
The acrylic was cut by snijlab.nl
A Dutch company.

I use this for my pool (and DIY solar pool heater)

@AWI
Thank you for answer.
See this link for an project based in this.
Its basically a scène controller in the shape of a cube.
I got the idea from the original poster in the thread over at home-assistant.

https://community.home-assistant.io/t/rubiks-mood-cube-magic-cube/9965/8

I will post a BOM, sketch and pics if someone wants me to.