Hi there!

I'm gathering the ideas of poorman's photography in the area of light-sensitive materials. When I write "Poorman's" I could also write "DIY-ish", "natural" or "eco".

So far I've been able to find very few:
Egg's white is supposed to harden (become insoluble, like gum in bichromate processes) in daylight without sensitizing,
Extracts from flower petals are bleaching under the sunlight,
Leaves do the same thing.

Do you know any other ways to make poorman's photos (this things may be expensive, but should not include industry level chemicals/materials, but rather things you can find or do on your own)?
Are there any poorman's ways to fix such photos?

The only two photographical "instruments" are pinhole camera and directly casting shadows (when objects are near paper). I'm feeling this is nearly all.