I posted "Making case for a top " back in August based on geometries and harmonic numbers which I just briefly discussed. The following Is one geometry I use often, it is basically a trapezoid with 8 equal angles and 4 equal sides which it makes it a "Diamond". I can not show everything otherwise it would be be too confusing so I kept it simple. In addition, is a circle encompassing 3 vertices quite powerful in itself. http://screencast.com/t/pp57lWGTdXLu click image to full screen