One of the chaps here is changing job titles, so he's got a few old business cards to spare. Ergo, mad card folding following Ned Batchelder's great instructions.

What we have in these pictures is a simple Menger's Sponge (depth 1), I think the eventual goal is a depth 2 sponge as in this picture. Then again, Gavin is certainly daft enough to attempt the level 3 sponge...

Quick fag packet maths: one cube is 6 cards, level 1 sponge is 20 cubes (120 cards), a level 2 sponge is 20 level 1 sponges (2400 cards), a level 3 sponge is 20 level 2 sponges (48000 cards); I guess we're safe for while, I don't think we've got *that* many cards to spare!