Nigerian banker Jim Ovia founded Zenith Bank Group, one of Nigeria's largest financial services groups, with a market capitalization of more than $4 billion. He is the bank's largest individual shareholder, with a 9% stake. He owns dozens of prime properties in pricey Nigerian neighborhoods like Victoria Island and Ikoyi. Ovia also runs Visafone, a mobile telecoms outfit, and is partnering with Marriott to build a new five star hotel in Lagos.