Cloaca is a conceptual art installation by the Belgian artist Wim Delvoye. It is a machine that simulates a digestive tract: Food can be fed to a transparent bowl at one end, and it then passes through a series of tubes and containers, until a feces-like substance is ejected at the other end.

Delvoye sells the (realistically smelling) output for 1500 EUR a piece. According to him, "it is selling very well".

According to Delvoye, the art piece is a comment to the pointlessness of modern life. He wanted to build the most useless machine – one that reduces food to waste.