If you have a Java-enabled browser, try out the latest reincarnation of the Fast Fourier transform lab. The source code is freely available.
You may download a copy of the paper Atomic meshes: from seismic images to reservoir simulation, published in September, 2002, in the proceedings of the 8th European Conference on the Mathematics of Oil Recovery. An earlier related paper Atomic images: a method for meshing digital images, was published in October, 2001, in the proceedings of the 10th International Meshing Roundtable.