Ever wanted to control Ardour using a little python script?
So that you dont have to click Play & stop, but can use your
Arduino, or maybe a MIDI device? Or if your just in the mood
for some Python fun, and wouldnt mind making something useful
to youself, here’s the PyArdour library.
There’s a class in the library, which will communicate with Ardour
via OSC, and only depends on liblo. (Which you will have since
your running ardour… 
PyLiblo is the python bindings for Liblo, which will need to be
found/installed/compiled/whatever depending on your setup.
Here’s the link: http://harryhaaren.blogspot.com/2009/12/tut-6-ardour-control-using-osc-python.html
Good luck! -Harry