Okay, it's an "intake vortex" of water in an Oklahoma waterway, but it looks like a giant endless black hole of sludge, which is how human interaction on the Internet feels sometimes.
"Here's a very unique view of an intake vortex, created as water enters the Denison Dam spillway on Lake Texoma. The vortex is approximately 8 feet in diameter and capable of sucking in a full-sized boat, so please heed all safety buoys and caution signs."
[Facebook via Reddit]