What is Jew's Ear Fungus

Actually, I'm not sure I want to know... I saw this Asian product on The Tonight Show with Jay Leno and looked into it. Roxy Instant Jew's Ear Fungus is manufactured by Roxy Country in China. Ingredients include Jew's Ear Fungus, Salt, and Potassium Sorbate. The website announces: "Introducing the new Instant Jew's Ear Fungus made with the finest natural Jew's Ear Fungus served with traditional ready mixed seasoning package."

I still have no idea what Jew's Ear Fungus is supposed to be, but I'm sure it's a delicacy somewhere in the world!