Playing around with 3-dimensional models is fun! Constructing those in an editor, printing, but also simply viewing in the browser.
This 3D model is created by NASA and made available by the Smithsonian Institution. Source
The Khronos archive has many nice looking 3D models. Source
I have no real use for this transformer, a 700 gram piece of copper and iron, a classic symbol of electric power engineering. But it would make a perfect paperweight, if only the bare metal would not scratch my nice table top. So I needed a plastic baseplate. This was the first attempt at making something useful with my new (pre-owned) 3D printer, a CReality Ender V2. To show it was really me who made this, I added my signature on the underside. I designed this 3D model with FreeCAD.