Free 3D CAM Programs: FreeMILL & PyCAM Overview

If you want to step up from 2.5D projects and do some "real" 3D milling, can you do it without spending money on a CAM program? Keeping my promise of being open-minded and trying out other CAM software, this week I'm looking at two options.
More info about the STL file format: en.wikipedia.or...
Disclaimer: This video cannot take the place of a proper tutorial.
Programs Used:
pycam.sourcefor...
mecsoft.com/fre...
openscam.com/ (visualization)