1990, the first Fun item I built on a SLA 250 was this 3D puzzle with Frank Green & Lasercad A 3D systems engineer gave me the STL file about 26 years ago. Half way through the build it was paused and the metal ball bearing was dropped in. Clients loved to play with this and guess how?

I do not think that this can be done now on the small vat SLA machines & even Carbon3D, unless the ball is made as a separate resin item, with clever supports that can be cut off? This is something I would like to have a go at.

3DPmuseum dot com