The best way to simulate percolation is with the use of the Hoshen-Kopelman algorithm.
Ido Braslavsky and Zaher Salman
PGPLOT versions of the
program given by Gould and Tobochnik. These can be downloaded
look at the source file pro.f and download the executable for either
linux (pro_lin.ex) or sun (tx).
Percolation does not only apply to uniform balls on a lattice. It is
also relevant for
continuum disks of spheres of different sizes. David Saada prepared
a routine to model this, which can be downloaded
Look at perco.f and download correct version for your computer.
The rich structure within percolation clusters has been explored by Eduardo
Lastly, and recommended because of the nice collection of links,
despite some bugs,
Nir Yefet has made three dimensional models of percolation clusters
using mesa. His webpage with lots of good links (including a link to another
percolation program in MATLAB) is
here. From these links you can find other links, at last count I
found about 10 distinct sites, many with
java applets. These will run
over netscape at the Technion if it is set correctly (enable java under the
edit preferences advanced option.) They may overtax the system resources
however (and crash your session), be warned. The algorithm description in this project has a bug in it, be warned.