A recent project for the science museum made me experiment with 3D in flash. (without using papervision). I created this example just using vectors and as3, but the possibilities for making an efficient page turn effect just in flash using movieclips can work very well. You can even evolve this for making a pop up book. See the test page here
This project evolved into using png 3d renders but would like to make an illustrated pop up book for a future project!
See the final popup book here – http://www.sciencemuseum.org.uk/broughttolife/themes/birthanddeath/childbirth.aspx
See more from this project here – http://www.spotdesign.co.uk/portfolio/science-museum-black-death/