Curtains Create Pinhole Camera

There are many instances of pinhole cameras being formed in darkened rooms to project the outside on a far wall. (Abelardo Morell has done work like this for example.) Two days ago, someone on Reddit shared what was happening with their curtains, and it was pretty fun:

That's the street below being projected sort of "accidentally" on his ceiling as a pinhole camera would do. Here's a video of the street below "moving" on his ceiling:

The curtains in my room create a "natural" pinhole camera that projects images of the street below onto my ceiling from r/woahdude

Click here to see it on Reddit if that embedded video doesn't work.