Founder of the Carnegie Steel Company, Carnegie is perhaps even more famous for giving his fortune away.
After selling his steel behemoth to J.P. Morgan's U.S. Steel, Carnegie established a number of philanthropic and non-profit organizations including the Carnegie Corporation, the Carnegie Endowment for International Peace, and nearly 3,000 public libraries.
A "man who dies rich dies disgraced," he wrote in Wealth, his most famous essay.