Sometimes it’s fun to do things just because they are interesting. This idea seems to be behind minimalist programming languages (languages with barely enough keywords to be viable). These languages have no useful purpose except to pose a challenge to programmers using them. Here’s one I played with on the Arduino.
A long time ago (2012) I wrote an application called MultiBlink that allowed me to control many simultaneous independent monochrome LEDs lighting in patterns. The original version was updated a number of times, gaining more features (and complexity) with each iteration. Recently I updated MultiBlink to version 5, which included a conversion to using neopixel type RGB LEDs controlled using the FastLED library.