There's a row of 8 lenses on the shelf. I couldn't decide which one to use. So I made a leeeetle hole in a piece of thick ally foil and used that instead. Yeah, I know. This has got to be the worst picture in the 500 or so in my PotD gallery. But without a doubt, it's the best one taken without a lens. And, I've taken a fair few pictures with a lens that aren't this sharp...
See another pinhole pic here and the pinhole itself here
BTW, it's a great way to see how dirty your sensor is. Looks like there's a couple of planks of wood on mine...