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Why, build a level three Menger Sponge, of course! What the heck is a Menger Sponge? Glad you asked. It’s a three-dimensional fractcal cube of sorts, first described by Austrian mathematician Karl Menger in 1926. When, some seventy years later, Dr. Jeannine Mosely found herself confronted with a gargantuan pile of business cards, rendered useless after the company she worked for changed addresses, she knew what she had to do with them: hand-make a real, live Menger Sponge — creating an actual object from something that had previously been merely a mathematical abstraction — a (sorta nerdy) feat of Guinness Book proportions. Before we show you how she made one in reality, a quickie guide to making them in the abstract:
1. Begin with a cube.
2. Divide every face of the cube into 9 squares. This will sub-divide the cube into 27 smaller cubes, like a Rubik’s Cube
3. Remove the cube at the middle of every face, and remove the cube in the center, leaving 20 cubes (second image). This is a Level 1 Menger sponge.
4. Repeat steps 1-3 for each of the remaining smaller cubes.

66,048 business cards, 8,000 business card cubes (Menger subunits) and 150 pounds of cube later, it was finished. Figuring the whole project required about 600 hours to build, she recruited volunteers from around the country to build parts of it and then ship them to her. Construction photos after the jump!
First, you’ve got to make a cube from six business cards — without staples, tape or glue — which Dr. Mosely describes how to do:
To make a cube out of six business cards, first take two cards and place them across each other at right angles, centering them as nearly as possible. Fold the flaps of the bottom card down over the top card. Turn them over and repeat. Pull the two cards apart. Six of them can be assembled as shown below to make a cube. All flaps must be on the outside of the finished cube.

For a super-detailed (and kinda math-y) description of how Mosely accomplished the rest of her fractal feat, check out this page at the aptly-named Institute for Figuring. Meanwhile, we’ll skip right to the pictures:


Photo by Ravi Apte
That is just entirely too cool. I see she’s wearing an OrigamiUSA shirt too… must be a fellow member!
posted by Jason! on 8-6-2007 at 1:25 pm
Finally found someone with big paper-related goals! (Trying to create a globe of OXO modules from scrap)
posted by Marcus on 8-6-2007 at 6:08 pm
Wow, that’s nothing short of amazing. So no staples or clue?? I think we know how the pyramids were built.
posted by Live TV on 8-6-2007 at 11:51 pm
WOW! If only I had that many business cards and that much time… simply amazing!
posted by Matt Smith on 8-6-2007 at 11:58 pm
holy shit thats awsome
posted by Adam on 8-7-2007 at 12:09 am
this is awesome.
she so looks like a geek. long live teh geeks!
posted by jesse on 8-7-2007 at 12:14 am
The thing that amazed me was the simple act of building the little cubes without “staples, glue or tape”. To figure that out was genius.
I think this is a cool project and the fact that she was able to make other people collaborate on it was an awesome idea too.
The last picture is pretty self explanatory. This is obviously a fellow geek. :)
posted by Auto Parts for Brains on 8-7-2007 at 12:23 am
Opps…it is not so create such things with paper. She is great.
posted by Gopinath M on 8-7-2007 at 12:23 am
This is soooo cooool. actually, i think its a little dorky
posted by Jessica on 8-7-2007 at 12:26 am
This is totally awesome! Back in our Freshman year of high school, my best friend and I constructed a figure of similar design– a Sierpinski pyramid. It was essentially the same idea, except it consisted of many small paper tetrahedrons. Connecting the tetrahedrons proved to be quite a challenge. It was a rather epic task for just the two of us (18 inches on a side), and to this day we still find small pieces of tape strewn about his basement :)
posted by Peter on 8-7-2007 at 12:33 am
Fraud! Clearly the lighter 3×3 square, to the right of her left elbow (to her right as we look at the photo) does not have its centre square removed.
posted by Bob Holness on 8-7-2007 at 1:52 am
truly amazing! thumbs up!!!
posted by Ritter99 on 8-7-2007 at 2:56 am
That is so awesome, I wish I had that much free time and I might attempt something as utterly remarkable. I’m feeling inspired!
posted by Mark Hankins on 8-7-2007 at 3:09 am
I bow in respect of your attention to detail, your tenacity, and clearly your wisdom in doing something really good once and for all with all those cards.
Gassho
posted by TizzyD on 8-7-2007 at 3:30 am
aww… I wish my company gave me business cards…
posted by Allan on 8-7-2007 at 4:28 am
I would love to see a video clip of her jumping off a table onto the cube. The packed air should cushion her fall.
Resistance is futile!
posted by Giacomo on 8-7-2007 at 4:50 am
That is soo cool but took so much time.
posted by Adam on 8-7-2007 at 5:05 am
she looks like a cool person.
posted by sam on 8-7-2007 at 5:21 am
Now that is determination ! Fair play to the girl.
posted by Becky @ PreBlogging on 8-7-2007 at 5:58 am
Looks great I might just give this a go with all the old colorful business cards in the closet over @ askTheAdmin.com.
posted by AskTheAdmin on 8-7-2007 at 7:48 am
Bob Holness, that lighter “box” is a sheet of paper placed on the cubes, probably set to identify the menger cube.
posted by Kevin on 8-7-2007 at 8:21 am
This is a great way to utilize un-usable paper business cards. This is just another reason why everyone should have an online business card that can be changed at any time for any reason. Check out Lyro.com. Thanks to Dr. Jeannine Mosely for helping prove our product!
posted by Robyn on 8-7-2007 at 9:23 am
Was a coworker of the artist. She’s got a doctorate in math from MIT. And a spinning wheel collection.
Yes, a fellow geek.
posted by ringo on 8-7-2007 at 9:31 am
Aha… the magic combination is way too much free time AND way too many business cards. I knew I was missing something!
posted by Dan on 8-7-2007 at 10:04 am
I wonder if her boyfriend/husband helped with it.
Probably not. ;-)
posted by Drew Vogel on 8-7-2007 at 10:04 am
One question…did she do this during business hours?
The time involved to do this must have been a while.
posted by The Dog on 8-7-2007 at 11:29 am
Too much spare time…
posted by Aidan Henry on 8-7-2007 at 11:52 am
Still no cure for cancer…
neat idea, but it’s also kind of sad when people spend such crazy amounts of time on what is largely a pointless pursuit… it would be one thing if we had no major problems pending that require peoples’ attention. Sad.. very sad.
It’s a shame they don’t give out Nobel Prizes for wasting shitloads of time.
posted by critical thinking news on 8-7-2007 at 12:08 pm
Alternatively, she could have just visited Lyro.com, the world’s largest database of DIGITAL business cards.
posted by Cool on 8-7-2007 at 12:20 pm
finally, something to do with all of my old ‘Magic:the gathering cards’…
posted by Ken on 8-7-2007 at 2:00 pm
Next up, Sierpinski’s Triangle?
posted by Barionic on 8-7-2007 at 5:41 pm
I think some people are jealous. This is really awesome. Just because she didnt cure cancer and made this awesome recycled Menger Sponge doesnt mean she wasted her time. Its better then wasting your time blogging and criticizing other’s accomplishments.
posted by thomasina on 8-7-2007 at 5:55 pm
This girl is a genius and patient. Wish I had 1/10 of the patience she had to have had to build this thing!
posted by Song on 8-7-2007 at 6:05 pm
Wow, I would not have been able to sit down for that long… Looks great, I should start collecting cards to make a smaller version. :)
posted by Alan Parekh on 8-7-2007 at 9:34 pm
critical thinking news: I suppose you spend every waking moment working on epic projects to benefit mankind. You must never waste any time playing video games, or watching TV, or trolling blogs, or any number of entertaining yet non-productive pursuits. Give the woman some credit. It may not be a cure for cancer but it did bring a big smile to my face. And that simple fact makes her accomplishment worthwhile.
posted by Alan on 8-7-2007 at 11:58 pm
Am I mistaken or would that only use 48,000 of the cards? What happened to the other 18,000? Something equally as nifty I hope.
posted by Jeff on 8-8-2007 at 2:57 pm
A minger sponge!
posted by Billy Bob on 8-9-2007 at 12:43 pm
Menger sponge! I’d never heard of one before…That is pretty cool.
And to the person who said that the light-colored block to the right of her elbow does not have its center cube taken out- I think that’s some sort of sign or piece of paper sitting on top of the cube.
posted by Domino on 9-10-2007 at 7:49 pm
Wow! That would make a cool building.
posted by Dave on 9-11-2007 at 10:01 pm
If she can do something like that with junk mail, I will get on board.
posted by skip on 9-12-2007 at 11:30 am
This is amazing. Im sure it took a lot of time and concentration to complete this. The lady is a genis.
posted by watch tv online on 4-24-2008 at 2:04 pm
Hi,
That’s amazing.
Good designs for cards.
posted by Hotel key card printing on 7-22-2008 at 2:20 am
Amazing. How much time went into those?
posted by austin_mls realtor on 8-17-2008 at 12:52 pm