From: sean@aries.scs.uiuc.edu (Sean Murphy)
Subject: Hallusion info??
Summary: Hallusion info?
Keywords: hallusion, 3d
Organization: University of Illinois at Urbana
Lines: 5

Has anyone seen hallusions?  You can buy a poster of them and it looks like a simple dot pattern
when you first look at it but if you focus behind it you see a 3d picture.  I'm looking for
a program that generates these pictures.  There's a company in Texas that makes them but I 
doubt if they're giving the program away.  Any help would be appreciated.