Loved by "New Scientist" magazine! See the 30 July 1994 issue cover and page 35!
The TEX files below are in plain TEX and require no macro files. You need to have a DVI / POSTSCRIPT / PDF viewer hooked into your browser to look at the DVI / POSTSCRIPT / PDF files. I have converted some of the files into ASCII and might convert the others soon. If anyone has already done this, I would be most interested.