I was playing around with a wallet-folded card like this one
www [dot] craftster.org/forum/index.php?topic=220731.0
the other day, wondering what would happen if I turned it inside out. Well, what happened was it fell apart (oops). But then I ended up with a sort of cool never-ending card thingy. You can turn it on the diamond and open it horizontally and then vertically, (10 sides available for pictures)

or you can glue it down and open it from the corners (8 sides available for pictures).




Tutorials here: extremecards [dot] blogspot.com/2008/08/10-faced-never-ending-card.html

and here: extremecards [dot] blogspot.com/2008/08/snapshots.html