Signs

A sign is tilted at an angle at around 15 degrees, It appears to have writing on it. The sign is one giant plank nailed to another, smaller plank, being the post.

You can press E to interact with the sign, and see what it says.

Signs were also sources of a quick and efficient camera launch bug, which lets the camera go in a certain direction without the player moving at all. This ends up turning into a noclip bug when the blocks are unloaded as they have been moved offscreen.