Created by: Valerie Vann, Jeannine Mosely
Published in: unknown
This was mentioned on the O-list, and looked interesting.
It is interesting, if a bit surprisingly tricky to assemble. I had trouble getting everything to fit, and getting tidy corners. (Plus the biz cards I used were a bit old, and cracked somewhat when I folded them.) Apparently it was independently discovered by both Valerie Vann and Jeannine Mosely.
I asked Jeannine about it, and it turns out you have to be careful fitting the tabs inside so that the various pieces don’t interfere with each other when you’re sliding things together. If you do it right, the corners get tighter, and you don’t get the little holes like the ones you can see in the photo.
The diagrams for this used to be online; if anyone knows where Valerie Vann’s modular origami page went, do let me know!
Super-delayed update: (2013!) Just recently, some googling yielding some surprising results – the Internet Archive Wayback Machine website had some tidbits from the now-defunct Vann site, including the basic folding pattern for this piece, though not the assembly images. So you’ll have to experiment a bit if you want to try it!
More updates: Also recently found Malachi Brown’s Business Card Origami page, where he calls it the “Diamond Edge Unit”, and has links to instructions for it.