Just a little doodle to set me thinking. Even limiting myself to concentric circles for the most part, I kept coming up with possibilities for using Volvelles. I started with the idea of surveying what could be done with a circle and a pivot. Information can be obscured, indicated, or illuminated with a Volvelle. The second circle below could be a changing face. I’m not sure how you illustrate or derive a function with such a thing. But, like I say, “just a little doodle.” Transparent colored circles could illustrate combinations and layered traces could illustrate circuits. The final Volvelle on the bottom right plays with the idea of a spiral around a pivot, that is a turntable. Is the needle on the top or the bottom? Is there a needle guide? Maybe musicians could use them to demonstrate a musical passage. Just run an amplifying stylus through the grooves and you have yourselves a tune.