I recommend TurboWarp and Turbo mode. It is a demonstration of the integral of sqrt(1-x^2) from 0 to 1; it calculates it by finding the area of the quadrilaterals that are shown by the lines that aren't part of the circle.
I really like pi. This is my 3rd project calculating it. I most likely will in the future release a project in where you can substitute the integral for a different one.
