Hey,
I've updated the script with some more tests and other goodies.
http://www.imitationpickles.org/tmp/safe.py
Regarding the stuff you mentioned - yah, it'll be interesting to see where PyPy goes. As for embeding another language in Galcon - I did consider embedding lua - it's pretty secure. But after mulling it over, I figured I'd much rather have python bots, and warn users about the danger of downloading and running strange bots.