Silk is a website that touts itself as “Interactive Generative Art”. Since this is Fun Friday, I feel okay about sharing this site with very little practical educational value because it is entertaining and, actually, a bit meditative. The concept is simple – use your mouse to start drawing. Once you begin, a tool palette will appear in the top left, allowing you to go full screen, save your picture, reveal the controls, undo, share, and start new. If you share, the link provided will actually show the construction of your design.
Music plays as you draw. This might be a good center for students who need to calm down, or to get their minds off some of the problems at home. It also can be used to teach symmetry. Or, you can use it for no reason at all, other than that you feel the need to create something beautiful.
There is an iOS app of Silk, but it is 99 cents. While you have the chance, I advise you to play the web version for free.