Cubing the sphere
Well, umm, I ran out of shampoo? And I was quite surprised to find that my head approximates a sphere rather well... so, assuming a spherical physicist, the following origami puzzle folds into a two inch cube:



If you're feeling a tenth as goofy as I am, print out the large version here, cut out the whole square, and fold...

The brown lines are "hill folds," with the paper folding up away from the front and creating an edge facing you, and the green lines are "valley folds," with the paper folding back and making an edge away from you. The strategy I recommend is to crease the paper in the right directions first along all the fold lines, then assemble the whole thing, folding the resulting flaps in on themselves starting with the cluster of folds in the lower right, until it holds together tightly as a cube, with only faces showing. It's kind of tricky. :) Please send me a comment or email if you make it, as I'd like to keep track of who has my head...

Ahh, they also make nice atheist x-mas ornaments, to go along with the other bulbs. Hee.