Enter casu marzu, a traditional Sardinian cheese made of sheep's milk—and maggots. Lots of maggots. Casu marzu starts out as your standard wheel of pecorino, but mongers leave it sitting outside to allow the cheese fly Piophila casei to fill it with eggs. A fly can lay hundreds of eggs in a single go, so it doesn't take much to impregnate the entire wheel with wriggling larvae. Those larvae eat the cheese, and their digestive juices break it down into a softer, creamier product than the original.