Sliceforms are “are geometric models constructed from interlocking sets of planar pieces,” basically a 3D model made of flat pieces, creating a grid. Mathematically-minded folks, of course, can create super complex structures with the technique, but it can be scaled down to make simpler structures, like this 3D Christmas tree. Extreme Cards provides a template, which can be used to print on whatever paper you’d like and cut by hand, or a vector file for machines like the Silhouette SD/Craft Robo. It can be easily translated into a pop-up card, as it can be flattened!
Sliceform Christmas Tree [Extreme Cards]