This is the long version of the file used for submission   
to the fourth short code contest (SCC).  Since I use random
numbers in the main code, I used this to choose the best
seed for the job.  So, the final result reflects my personal
sense of aesthetics just a bit.

The most amazing thing for me about this is the number of   
curves you can get from a bunch of flat surfaces (as long as
they are refractive).

The way the curves come about is due to the angle at which the
ray intersects the refracting surface.  As the angle changes, 
so does the degree of refraction.  If you want to see a real  
world example of this, stick your face right up to a fish tank
some time and look at one of the edges of the other side.  The
perfectly flat surface on the other side of the tank will look
like it is bowing outward, away from you.

My only regret is that I couldn't think of a short way to get
dispersion in here as well.  It looked really cool.

In order to find a nice combination of random seed and number
of boxes, I included the following code

#declare MAX=16 ;
#declare KK=floor(clock/MAX) ;
#declare LL=clock-MAX*floor(clock/MAX) ;
#debug concat("clock = ",str(clock,3,3),"\n")
#debug concat("KK = ",str(KK,3,3),"\n")
#debug concat("LL = ",str(LL,3,3),"\n")

changed the following lines,

#local S=seed(1) -> #local S=seed(KK);
#while(C<8) -> #while(C<LL)

and then ran with the options

+KFI0 +KFF255 +KI0 +KF255

to generate a whole range of images, from which I chose the one
I liked best for the final submission.  The whole thing should
only take a few seconds to render.