Icosahedron (Nick Robinson's trimodule)

Folded over the span of two days.  Pretty simple units to fold, but difficult to put together because they do not lock very well.  Folding instructions for the unit can be found on Nick Robinson's website.  It's a nice unit that can be used to fold both 2D and 3D models.  I will fold a few flat models later, but here is a 3D one for now.

Very simple unit.  Needed 30 of these.

The units fit together in groups of three.  I am usually an origami purist, but tape/glue would have made this a lot easier.

One ah-ah-ah, Two ah-ah-ah, Three ah-ah-ah...

The final model looks good and seems pretty solid now that all the pieces are in place.  With an acute angle formed between each spike, it locks the units together pretty well.

20 Spikes total. ^_^

Level One Menger Sponge

"In mathematics, the Menger sponge is a fractal curve. It is a universal curve, in that it has topological dimension one, and any other curve (more precisely: any compact metric space of topological dimension 1) is homeomorphic to some subset of it. It is sometimes called the Menger-Sierpinski sponge or the Sierpinski sponge. It is a three-dimensional extension of the Cantor set and Sierpinski carpet. It was first described by Karl Menger (1926) while exploring the concept of topological dimension."

This specific model is made out of 120 Sonobe units.

I chose two complimenting colors and folded 72 of one color (silver) and 48 of the other (blue).  The different colors are almost identical.  The only difference is the side of the module that is folded.  Example below:

Note: Foil is highly overrated for origami.

A bunch of modules waiting to be assembled.

I first encountered the Sonobe unit in the book "Modular Origami Polyhedra".  It's a good book with a lot of neat models in it.  Assembling the cube is easy, but time consuming.  Alternate the colors and I recommend making one full side first and building up from there.

Keep adding the modules.  Just keep building, just keep building and eventually you will be rewarded with the completed model.  One level one Menger sponge.

There you go, the final model.   Took about a day to complete working on it slowly. ^_^