This sort of thing makes me wonder what the successor is to the Gingery Books now that they're going away:

https://gingerybookstore.com/

Chris Borges has done some pretty cool little machines using 3D printed forms filled with concrete:

https://www.printables.com/@ChrisBorge

and of course there are more CNC router designs than one can shake a stick at (ob. discl., I work for a company which makes one)