zzSpirograph Screensaver, modeled after the early 70's geometric drawing toy.
The actual toy consisted of preformed plastic shapes that when combined and used together, produce roulette curves - technically known as hypotrochoids and epitrochoids. A better explanation is it consisted of two different-sized plastic rings, with gear teeth on both the inside and outside of their circumferences. It consisted of multiple different-sized plastic rings, with gear teeth on both the inside and outside of their rims. You could pin any of several provided gearwheels to a cardboard backing. They all had holes for a pen or pencil to stick through. You could then work the smaller gear inside a larger one with the pen and mark out intricate geometric lines.
zzSpirograph Screensaver comes in a zip file as a .scr, which is typical of most screensavers. To use it, right-click on zzSpirograph.scr after extracting from the zip file and select "Install" or "Test" to preview it before installing it. The screensaver properties window will pop up to configure your settings; however, this particular screensaver has no additional settings other than allowing you to show the spirograph design without the geared rings as well as rotation of the outer ring.