I just read this article, and thought it was interesting, so thought I'd post it in case someone wanted to read it.
http://www.reptilechannel.com/turtles-and-tortoises/tortoise-care/pyramiding-in-tortoises.aspx
http://www.reptilechannel.com/turtles-and-tortoises/tortoise-care/pyramiding-in-tortoises.aspx