Chinese cooks do wonderful things with eggs. Duck, as both eggs and flesh is one of my favorite foods.
Duck eggs are quite expensive compared with hen eggs. A dozen hen eggs is under $3.00 (Feb. 2015 prices), while duck eggs range from 65¢ to $1.50 each. And the $1.50 is by the dozen.
While shopping in Chinatown, I found 5 for $4.00. Expensive, but I'll eat an egg for lunch with some other ingredient and that's going to be a fine meal.