reStructuredText, sphinx etc.

Presentations with restructuredtext:

http://lateral.netmanagers.com.ar/stories/BBS52.html - Creating presentations using reStructuredText. Using rst2pdf (which uses ReportLab's PDF generating software and is seriously cool). With links to nice tools for presenting the PDF documents afterwards.

One tool referred to is Impressive which can be used to show pdf's and just happens to be written in Python: http://impressive.sourceforge.net/

And also see the Bruce the presentation tool: http://code.google.com/p/bruce-tpt/