Half animal, half vegetable, the Cordyceps Sinensis is a unique combination of a caterpillar and a wild mushroom that grows at 13,000 feet on the high plateaus of Tibet. Renowned for its stimulating effects on the immune system, and also known as the "Viagra of the Himalayas," it has become the new El Dorado in the Chinese economy. With about a quarter of the world's population, both East and West, currently taking Chinese medicinal herbs, the market for Cordyceps is enormous.