I had a little play with pinhole photography today - I think I've done this before but I couldn't find the equipment so I built it again. The kits sold for digital cameras generally cost seven or eight quid for what is essentially a lens cap with a hole in the middle, so I cut out the middle man and build my own. This one was simply a 50p plastic body cap (you can get a rear lens cap and a body cap for £1 from Hong Kong) with a hole in the middle, and a strip of Meccano used to retain the actual pinhole, made in some aluminium foil. In an ideal world the hole would be micro-drilled and the foil would be replaced by a sheet of matt black plastic, but this was a basic test so I didn't bother.
Results are pretty dire, and basically confirm that this works, that lenses work much better, and that I really need to clean my camera's sensor - because of the way they work, pinholes reveal any crud that's there, even if it wouldn't normally affect the image if a lens was used.
I tried some artistic effects which worked quite well - but to be honest, they'd probably work just as well on images from a normal lens. On the whole I think it's an interesting experiment, and I may try to improve on it, but I'm not going to waste a huge amount of time on it. I've reduced the size of the images since they aren't that exciting. Pinhole lens cap