The cameras are really easy to make (disposable) and require no chemistry to develop. You end up with a color-like negative using simple black and white photo paper. Here are a couple related howtos:

http://www.pinholephotography.org/Solargraph%20instructions....

http://www.solargraphy.com/index.php?option=com_content&...

great idea.

i made a pinhole camera a few years back from an oatmeal cylinder. here's a picture of 77 Mass Ave

http://bilumi.org/lucy/OATMEALPINHOLE.jpg

Wow, excellent find. I lived in Bristol up until recently and you can faintly see my old home in the Clifton Suspension Bridge image!