Have you ever heard of, or seen a Never Ending Card? What looks like four cards below, is actually just one card. When you open the folds, another panel appears, then open again, and again and again. It just keeps unfolding, finally repeating the same view. There is a great tutorial at Splitcoast Stampers. You have to register to access the free site, but there is a wealth of information on that site!
I was totally prepared to mess up at least once while making it the first time. I didn't plan the design well because of that. The video tutorial was so well done, my first attempt came out perfectly.
Here is a link to the tutorial I used:
All the measurements are shown on the video, but just in case you'd like to have a written copy:
Whisper White cardstock (or base color)
4 pieces 3 x 6
score on the long side 1 ½ and 4 ½
rotate 90̊ score 1 ½ from top to the intersect (previous score line)
rotate again 180̊ score 1 ½ from top to intersect
rotate 90̊ score 1 ½ from top to the intersect
Coordinating designer series paper or cardstock
8 pieces 2 ¾ squares
4 pieces 2 ¾ x 1 ¼
16 pieces 1 ¼ squares