Of the many 'rags to riches' stories in US history, Andrew Carnegie's is one of the most fascinating. After immigrating from Scotland when he was a child, he worked his way up through a telegraph company, and with sheer determination and hard work, his investments in the railroads and steel made him one of the richest man in the world. This story wouldn't be so interesting if he'd died with all of his loot: before he kicked the bucket he had given away 90% of his money. His philanthropy funded thousands of libraries, music halls and parks that were free to the public. Super-rich computer moguls today are left with this legacy, and it seems like Bill Gates and Paul Allen are following his lead. But even average business-minded folks today can read Carnegie's autobiography for such a takeaway. Here is a look into the life and mind of one of history's richest men-in both wealth and character.