As is my wont, I calculate pi. It's considerably more efficient than my last effort, though that's to be expected given the methodology.
As I mentioned earlier, I've been playing with Python, and I've a long-standing tradition, dating back to high school, of calculating pi when I'm starting to learn a new computer language.
That ugly-looking
d = math.sqrt((c*c) + pow((1 - math.sqrt(1-(c*c))),2))