I like this word, kaleidoscopic, I can’t always spell it but it’s something I remember as a child’s toy. A tube you rotate and glass or plastic pieces fall in an enclosed end of the tube so that when you look through the eyepiece they change patterns. The inside of the rest of the tube has mirrors along the length of it so the image is split into sections like a sliced up pie.

It’s difficult to try and explain exactly how it works without taking one apart but you get beautiful patterns similar to the image above (this is just some patterned cloth).