Conversation so far:
How did Warren Buffett become a billionaire?
Buffett became a billionaire when Berkshire Hathaway began selling class A shares.
When did Warren Buffett become a billionaire?
Buffett became a billionaire on May 29, 1990, with the market closing at $7,175 a share.
How did Warren Buffett feel about personal wealth?
Buffett had long stated his intention to give away his fortune to charity.
What foundations did Warren Buffett contribute his wealth towards?
He pledged about the equivalent of 10 million Berkshire Hathaway Class B shares to the Bill & Melinda Gates Foundation, making it the largest charitable donation in history.

Question: Are there any other interesting aspects about this article?
Self-contained rewrite: Are there any other interesting aspects about this article on Warren Buffett besides his becoming a billionaire and charitable contributions?