At Berkshire Hathaway’s annual meeting earlier this year, Warren Buffett showed just how much of a fan he is of Apple’s CEO, Tim Cook. “Tim Cook has made Berkshire a lot more than I have made Berkshire,” Buffett said to laughter in the room. It was funny, but considering that Apple is Berkshire’s largest holding, I don’t think it was hyperbole.

Thanks partly to Bogle, Buffett once won a $1 million bet that a Vanguard S&P index fund would outperform a selection of top hedge funds.

Warren Buffett is occasionally granted the "confidential treatment" tag, which allows him to build up Berkshire Hathaway's stake in one or more securities in secrecy. Buffett's newly revealed mystery stock -- a $1.