Menger sponges

I'm finally getting around to getting a class to fold a Menger sponge (Wikiread about them -- they are fun): we're going to fold the level 2 sponge, since it only requires a few thousand business cards, rather than 60 thousand for the level 3.  I do know of some people who have folded the level 3 sponge, notably Jeanette Mosely, who has observed that folding a level 4 sponge from business cards would be impossible: it would weigh a ton (literally) and would collapse under its own weight.
We folded two level 1 sponges at the end of tonight's class, and will fold the remaining level 0 cubes to make the 18 level 1 sponges remaining next week.  I hope to have some photos soon!

Yours, fractally speaking, approximately,
N.