Use the Source/Gnu's Not Unix
Get in depth on the GNU movement and FSF, more detailed description on how the whole lisp and emacs mess took place.
Talk about the GPL, the LGPL, the GPL2 and FDL.
Talk about the zeal involved in the movement and their opinion on the old BSD, new BSD and some of the other OSI certified open source licenses.
Talk also about their views on freedom and closed source software.