What to do with 66,000 business cards

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:
menger3.jpgmenger4.jpgmenger5.jpgPhoto by Ravi Ap

Quick True/False: World Capitals
Bain News Service - Library of Congress, Public Domain, Wikimedia Commons
10 Pats Born on St. Patrick's Day
A photo from the 1919 wedding of Princess Patricia of Connaught to the Hon. Alexander Ramsay.
A photo from the 1919 wedding of Princess Patricia of Connaught to the Hon. Alexander Ramsay.
Bain News Service - Library of Congress, Public Domain, Wikimedia Commons

Need some St. Patrick's Day conversation fodder that doesn't involve leprechauns or four-leaf clovers? Ask your friends to name a "Pat" born on St. Patrick's Day. If they can't, they owe you a drink—then you can wow them with this list of 10.


Princess Patricia was the granddaughter of Queen Victoria, who gave up all of her royal titles when she married a commoner. She was born at Buckingham Palace on March 17, 1886.


The Dallas star was born on March 17, 1949. And here's a totally random fact about Duffy: His nephew is Barry Zito, former MLB pitcher for the Oakland Athletics and the San Francisco Giants.


Pattie Boyd
Larry Ellis, Express/Getty Images

Pattie Boyd is well-known to lovers of classic rock: She has been married three times, including once to George Harrison and once to Eric Clapton, who both wrote a couple of the most romantic songs in rock history in her honor (including The Beatles's "Something" and Clapton's "Wonderful Tonight"). Boyd was a model when she met Harrison on the set of A Hard Day's Night in 1964; the pair were married two years later. They divorced in 1977 and she married Clapton, Harrison's close friend, in 1979. She also had an affair with Ronnie Wood of the Rolling Stones toward the end of her marriage to The Quiet Beatle.


Belfast-born Pat Rice is a former footballer and coach who spent the bulk of his career with Arsenal F.C. (that's "football club," a.k.a. soccer to us Americans). He joined the Gunners in 1964 as a mere apprentice, turning pro a couple of years later. He became captain in 1977 and left the club for a few years in the early 1980s to go to Watford, but returned after he retired from playing in 1984. In 2012, after nearly 30 years with the organization, he announced his retirement.


Patty Maloney is an actress with dwarfism who stands just three feet, 11 inches tall. She has appeared in many movies and T.V. shows over the years, including operating the Crypt Keeper puppet in Tales from the Crypt. She also played Chewbacca's son Lumpy in The Star Wars Holiday Special.


Michael C. Hall and Mathew St. Patrick in 'Six Feet Under'

Ok, so Mathew St. Patrick is the stage name of the actor, but he was born Patrick Matthews in Philadelphia on March 17, 1968. You probably know him best as David's boyfriend Keith on Six Feet Under.


He may not be a household name, but the recording artists Patrick Adams writes for and helps produce certainly are. Adams has been involved in the careers of Salt-N-Pepa, Sister Sledge, Gladys Knight, Rick James, and Coolio, among others.


It's possible you look at Patrick McDonnell's work every day, depending on which comics your newspaper carries. McDonnell draws a strip called Mutts featuring a dog and a cat named Earl and Mooch, respectively. Charles Schulz called it one of the best comic strips of all time.


 Singer/Guitarist Billy Corgan of Smashing Pumpkins performs onstage during Live Earth New York at Giants Stadium on July 7, 2007 in East Rutherford, New Jersey
Evan Agostini, Getty Images

Yes, you know him better as just plain old Billy Corgan: he's the face of the Smashing Pumpkins, engages in public feuds with Courtney Love, and maybe once dated Jessica Simpson. He made his debut on March 17, 1967.


Patricia Ford is a retired model probably best known for her Playboy photoshoots in the 1990s.


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