Test Driven Infrastructure (with examples in RPM packages).
How to save your butt by adding a few cheap and simple tests to your packages.
Use visudo to validate sudo configuration (sudo will stop to work with broken configs!).
Use bash and python to validate scripts against typos, forgotton braces etc.
I gave this talk at the PyConDE 2013 (https://2013.de.pycon.org/), Original video with all lightning talks is http://pyvideo.org/video/2438/mittwoch-lightning-talks