Divine Proportions

Here is something rather mathy.

Chris and Shannon both posted about it already, but it seems appropriate for me to.

This version of trigonometry uses quadrances and spreads instead of sines, cosines, tangents, etc. Quadrance is the distance between two points, squared. And spread is a way ot define how far apart two lines are using altitudes and ratios of quadrances. I didn't read all of the PDF, but it's interesting.