My hobby project is about using Lego mindstorms to turn a lathe / turning machine into a CNC.
One missing piece is the "CAM" part that takes a 3D model and produces gcode that determines the tool-path.
candidates are pycam, heekscad and maybe some others and as a fallback a simple self-made one.
CAMotics can already be used to simulate+visualize the resulting gcode.
This project is one of its kind!