Here's the Palomino pinhole camera I built a few weeks ago.
I made it with scraps from our wood shed and hand drilled the pinhole in some brass shim stock.
It works out to be F/214. I named it the "Palomino" for its color. You can't see it in the photo, but it has a little bit of sheen like a Palomino too.
This is the front
and here's a back view....