Here is some basic information:
Mengerâ€™s Sponge – named for its inventor Karl Menger and sometimes wrongly called Sierpinskiâ€™s Sponge â€“ was the first three dimensional fractal that mathematicians became aware of. In 1995 Dr Jeannine Mosely, a software engineer, set out to build a level 3 Menger Sponge from business cards. After 9 years of effort, involving hundreds of folders all over America, the Business Card Menger Sponge was completed. The resulting object is comprised of 66,048 cards folded into 8000 interlinked sub-cubes, with the entire surface paneled to reveal the Level 2 and Level 3 fractal iterations.
OTOH, if you have some time and patience and no math ability you just might be able to do this yourself.