The official name of this shape is Icosidodecahedron. But I just liked the star shape formed by the crisscrossing circles.
The pink one was my first attempt, figuring out how everything went together and where the slots had to go. Although the multi-colored one is marked up with pieces numbers and slot numbers, it looks pretty good. The heart one almost drove me mad! I'll put up the files for that, too, but it's definitely "try at your own risk."
Tutorial is up.
Extreme Cards and Papercrafting: pop up cards, movable and mechanical cards, digital crafts and unusual papercrafts.