Most Expensive Homes in the World

In Hong Kong, they gaze over the glittering city from the heights of the Peak. In Africa, they harbor elephants and lions. In Australia, they lie on the beach, of course.
The most expensive homes in the world may not seem to have much in common besides price -- and even those vary greatly, from $100 million-plus palaces in England and the United States to grand houses priced under $10 million in South