Have you heard of Balut?

A delicacy of Southeast Asia and especially the Philippines, a balut is a fertilized duck egg with a nearly-developed embryo inside that is boiled and eaten in the shell. Popularly believed to be an aphrodisiac and considered a hearty snack, balut are mostly sold by street vendors at night. Their high protein content is complimentary to the consumption of beer. The word balut roughly translates to mean "wrapped".
Balut are most often eaten with a pinch of salt, though some balut-eaters prefer chili and vinegar to complement their egg. The eggs are savored for their harmony of textures and flavors; the broth surrounding the embryo is sipped from the egg before the shell is peeled and the yolk and young chick inside can be eaten. All of the contents of the egg are consumed with the exception of a hard white chunk (the bato or "rock") that is found in the bottom of the egg. Balut have recently entered higher cuisine by being served as appetizers in restaurants: cooked adobo style, fried in omelettes or even used as filling in baked pastries.
Balut-making is not native to the Philippines. A similar preparation is known in China as maodan (Chinese: 毛蛋; pinyin: máodàn; literally "hairy egg"), and Chinese traders and migrants are said to have brought the idea of eating fertilized duck eggs to the Philippines. However, the knowledge and craft of balut-making has been localized by the balut-makers (mangbabalut). Today, balut production has not been mechanized in favor of the traditional production by hand. Although balut are produced throughout the Philippines, balut-makers in Pateros are renowned for their careful selection and incubation of the eggs.
Fertilized duck eggs are kept warm in the sun and stored in baskets to retain warmth. After nine days, the eggs are held to a light to reveal the zygote inside. Approximately eight days later the balut are ready to be cooked, sold, and eaten. Vendors sell cooked balut out of buckets of sand, used to retain warmth, and are accompanied by small packets of salt. Uncooked balut are rarely sold in Southeast Asia. In the United States, many Asian markets occasionally carry uncooked balut eggs, though their demand in North America is not very great. The cooking process is identical to that of hard-boiled chicken eggs, but the eggs are enjoyed while still warm.
Duck eggs that are not properly developed after nine to twelve days are sold as penoy, which look, smell and taste similar to a regular hard-boiled egg. These are occasionally beaten and fried, similar to scrambled eggs, and served with a vinegar dip.
The age of the egg before it can be cooked is a matter of colloquial preference. In the Philippines, the perfect balut is 17 days old, at which point it is said to be balut sa puti ("wrapped in white"). The chick inside is not old enough to show its beak, feathers or claws and the bones are undeveloped. The Vietnamese prefer their balut matured from 19 days up to 21 days, when the chick is old enough to be recognizable as a baby duck and has bones that will be firm but tender when cooked