Useful Math Visualizations

Over the years I've made some useful applications for people, which is very gratifying. Currently I'm seeing a program from a couple years ago come back around to see usefulness in the geometry classroom at my school due to the curiosity and insight of one of our math teachers, Matt DeGraff. He observed that such visualizations do aid in his students understanding of a problem and help them think about describing it in mathematical terms. His use of the program and our discussions about it are giving me the idea that a few different programs I've developed around it should be integrated into one to allow students to visualize a certain problem as an aide to seeing solutions and explaining them. Briefly, here are the three programs, more explanation to come:

Polygon vertex problem visualized as polygon