Just finished up 'calculator.py', which is available on the downloads page. Took me a total of about 1 or 2 working hours, most of which was spent looking up API calls for GTK, and figuring out a little bit of calculator logic (particularly, how to handle repeated presses to '=' gracefully).
(Please understand that calculator.py is messy, and this is my first attempt at a Python app that wasn't copied-and-pasted or 20 lines long, and my first real GTK app. Kudos to pygtk.org for having a decent tutorial section.)
Setting it up to work with peekaboo is trivial, and consists of adding a few lines in main(). I might do that, but leave it commented out if somebody wants to play with it for a few seconds, and doesn't have figleaf installed, and peekaboo handy.
Step two is going to be to automate a few keypresses using guitest. I might play around with dogtail as well, although it's been pretty well established that the method used by dogtail would prove hard to adapt to Sugar, due to its reliance on accessibility information. I still want to take a peek, perhaps to see how they structured the API? Might be worth it. Still no info from the GUITAR guys at SF.net.
Ecto insists on screwing with my paragraph spacing. FFS