Using NodeBox you can make images and movies from a small amount of python code. It is very fun. You can change the number literal by dragging it with command key. It is nice idea.
from math import sin, cos
SIZE = 431
size(SIZE, SIZE)
x = 19
y = 324
th = 1
dth = 0.5
ddth = 0.1
s = 30
colormode(RGB, 1)
stroke(color(0.5, 1, 0.5, 0.3))
strokewidth(2)
fill(color(0.5, 1, 0.5, 0.7))
beginpath()
moveto(x, y)
for i in range(313):
x += sin(th) * s
y += cos(th) * s
th += dth
dth += ddth
lineto(x, y)
print x, y
endpath()