Consumed is a computer animated short film by Andreas Wannerstedt. The short is completely CGI, and gorgeously made.
The story centers around a lab-made self replicating substance meant to replace food for an overpopulated planet, but through some error, the replication becomes uncontrollable, consuming the Earth. The concept behind this story resembles ideal population growth models of bacteria. If there existed, hypothetically, a bacteria population that successfully doubled in size every twenty minutes, and had unlimited resources with no death rate, then the Earth could be covered by this bacteria population in under two days. This wont happen because even though bacteria exist that can split every twenty minutes, not all reproductions are successful, and resources are limited, as we ourselves can see as overpopulation becomes a problem.