Grrrrrrrrrrrrrr,    It always works this way when you get older.   
Several weeks ago there was
a bunch of e-mails about ray-tracing and light pipes. I saved the 
summary that had the 2 web sites
listed,........................or so I thought.  After telling a 
coleague about it, I now cannot find it.
If anyone has the links to those sites I would greatly appreciate it.
Thanks in advance.