Much like the spirograph applet, but don't have to wait for the figure to draw. Can adjust inner design (both innerinner circle size and innerouter circle size and d1-where is pen in outer circle) and the outer design (both outerinner and outeroutercircle size and d2-where is pen in outer circle). Don't see the circles like you can at [url=http://www.mathplayground.com/Spiromath.html]http://www.mathplayground.com/Spiromath.html[/url]. But you can see both designs at once and adjust colors (background and of each spirograph design). Outer circle having negative size switches it to rotate inside the inner circle.