Polygon Pop Art
Two different rectangular grids of polygons that rotate at the same speed.
You can adjust the number of sides, size and starting position of each separately.
What can you make?
(Here's mine: http://mathhombre.tumblr.com/post/97240365074/polygon-popartgrid-not-sure-how-this-image-got)
More GeoGebra at bit.ly/mh-ggb