I was just listening to the BBC on the radio in my car. If you haven't heard about this, you should check it out: the Legacy Photo Project, here in California, did an amazing project last year using an airplane hanger as a camera obscura, or pinhole camera, to produce probably the world's largest photograph, made on specially-ordered German muslin without seams: three stories high by eleven stories long. The place is not beautiful, but it's an amazing piece of engineering and cooperative work, as you can see if you go to the Great Picture link and then click on the Fact Sheet.
I was nosing around the photography websites and seeing complaints of how lame the picture looks, but from what the guy I heard says, as you walk up close, the detail is amazing. If you go to the "gallery" link in "The Great Picture" section, second photo along shows some of the details. And all with a lens-less 1/4" pinhole.
Definitely a curiosity worth storing in the Cabinet - all 1200 pounds of it.