As part of a forthcoming planetarium show about the human brain, we are producing realistic models of the central nervous system at a variety of scales, from whole brain images to images of individual neurons. We have focused on the visual system and especially the visual cortex, and are building sets of simulated neurons using stochastic growth rules that mimic the geometries of actual neurons. We anticipate that some of the techniques we have developed in this work may also prove useful in various areas of computational neuroscience. 2000 Elsevier Science B.V. All rights reserved.