When doing some research on Matrix Algebra, I found some helpful determinant calculation code at anderswallin.net. In his word list, he has opencamlib. This gets into many blog entries getting heavy duty in to CNC tool placement and tracking. Cool.
Following along, I ended up on LinuxCNC's web site. LinuxCNC is a software system for computer control of machines such as milling machines, lathes, plasma cutters, cutting machines, robots, hexapods, etc. Given all the 3D printer systems, laser cutting systems, and CNC systems, this looks like a useful application to know about.