Any idea where I can find some, either in a store or on a restaurant menu? I've never tried it, and I'm getting more and more curious.
I think you mean the preserved duck egg in Chinese cuisine? also known as 1000 yr eggs. They are found at almost all Chinese grocery stores, usually still in the straw covering. (There is also the "chemically preserved version" which doesn't use straw but I only had it once and it was horrible!)
As it is very strong tasting it is not usually served by itself. At restaurants you may find it as dim sum in a pastry "pay dan so". In some restos you may find a dish called "triple eggs" which is chopped century egg and salted egg, fried in an omelette.
At home we cut it up and mix it with firm tofu cubes, with a soy sauce and sesame oil dressing.
My mom would serve them in quarters with pickled onions and tinned asparagus (yes, the tinny limp kind). It sounds terrible and I have no idea where this "dish" originated" but I'll admit to liking it.