Number 7: David Ross, UK: Net worth: $1.4 billion
Ross co-founded Carphone Warehouse, the European mobile-phone retailer, with school friend Charles Dunstone in 1989. An arts lover, he stages operas at his weekend home in the country. In fact, he built a concert hall on his front lawn for these occasions. In his London home, he has studios for three portrait painters to use. (Image courtesy: Reuters)