Pork Fu and Pork Sung (slightly different process) are very popular in Chinese cuisine, particularly as a topping to add flavor to bland ingredients such as rice congee and tofu. Most sold here in Los Angeles are from Taiwan.
These products are made by cooking pork in a soy sauce broth so long that all the connective tissue is dissolved out. The meat fibers can then be teased apart and dry fried to remove moisture. Sung has much shorter fibers, is dry fried longer and has more of the flavoring ingredients. Typical ingredients: pork, sugar, soy flour, soy sauce, lard, salt, msg.
Of course, I tell people pork floss is belly button lint collected from pigs. Imitations made of beef, fish, and chicken are made in Muslim regions of East and Southeast Asia, but I've seen none for sale here in Los Angeles.
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