Number 8: Sergei Polonsky, Russia: Net worth: $1.2 billion
A former architecture student, Polonsky is now one of the highest-profile real estate developers in Moscow. (His Mirax Group built the 1,300-foot Moscow City tower.) An extreme-sports lover, he hoped to fly on the International Space Station but was rejected because of his height. At 6 feet 4 inches, he is too tall. (Image courtesy: Reuters)