Lucia Contreras Flores has the most amazing collection of paper theaters and gives great insight into the history of toy theater. http://www.teatritos.com/uk/index.html You will be inspired by wonderful images such as this:
I am putting together some images right now for an animator named Stephen Coleman. He has some great images of historical paper theaters and tunnel books on his blog. http://agraphiablog.blogspot.com/2010/04/paper-theaters.html
His portfolio is here. http://coleman.myhosting.net/agraphia/resume/ I love how he has played with paper elements!