E.T. Container Instructions
Instructions below are predominantly pictoral. Start from a square. I recommend 8 inches or more paper that is the same color on both sides.
When you flip the container over you have a pyramid. From the vertices you are pinching the sides together all the way to the tip of the pyramid. Then you are going to pick a direction and have the three flaps going in one direction. (Refer to next photo) The center bit does not lie flat. It will form a smaller poofy pyramid as you keep push the three flaps. For the picture after I reverse folded the outermost triangular crease.
Now flip over and you will tuck in the tips.
Then on a preexisting crease fold the new tip back in. Do this on all three corners and turn over. Minor amusement is you can keep making smaller and smaller poofie triangles in the center. Hooray for fractal thingies (Example Below).
Lorenzo Marchi inspired me to play with the form. He uses it to create what he calls a triangular masu box. Directions can be found here. He also has a blog he periodically updates.