Warren Buffett Watch

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As a student at Harvard Business School, Tracy Britt Cool, 34, was given an assignment that asked her to imagine where she'd be in 10 years.

“My goal is to work with a great investor," she wrote, "who even more importantly is a wonderful teacher and mentor.”

Her vision was met with ridicule by a classmate, she admitted in a 2013 Lean In blog post. But at the age of 25, Cool was hired as the financial assistant and right-hand woman to Berkshire Hathaway CEO Warren Buffett.

How did this millennial manage to snag a coveted position working directly for the Oracle of Omaha? According to the Wall Street Journal, when Cool, a Kansas native, arrived for her interview with Buffett, who is from Nebraska, she brought the investor a “bushel of corn and a batch of tomatoes” from her family’s farm. She hoped that the folksy gesture would woo the billionaire — and it did.

But Cool’s journey to Omaha actually started well before 2009. In fact, her ascent began on her family’s fruit and vegetable farm just outside of Manhattan, Kansas.

“At around 10 years of age, I had my own farmer's market stand," Cool recalled in a 2014 interview with CNBC. "I hired my friends and set their wages, set the prices of fruit and vegetables, and I realized I liked all those aspects of business and that's what I wanted to go into.”

Former United States President Barack Obama believes that ballooning wealth inequality is a threat to society, and that those who have the means should help those who are less fortunate.

“Right now I’m actually surprised by how much money I got,” the 44th President said in his address to more than 10,000 people gathered in Johannesburg, South Africa, on Tuesday. “There’s only so much you can eat. There’s only so big a house you can have. There’s only so many nice trips you can take. I mean, it’s enough.”

The Obamas made more than $20 million between 2005 and 2016 thanks in large part to two lucrative book deals, according to an analysis by Forbes.

Wealthy people should give money to those who are less fortunate, Obama said in the speech, which was his highest-profile appearance since leaving office.

In the years from 2009 to 2015, Obama gave more than $1 million to charities, according to Forbes.

“You don’t have to take a vow of poverty just to say, ‘Well, let me help out... let me look at that child out there who doesn’t have enough to eat or needs some school fees, let me help him out. I’ll pay a little more in taxes. It’s okay. I can afford it,’” Obama said.

“I mean, it shows a poverty of ambition to just want to take more and more and more, instead of saying, ‘Wow, I’ve got so much. Who can I help? How can I give more and more and more?’ That’s ambition. That’s impact. That’s influence. What an amazing gift to be able to help people, not just yourself.”

There have been significant improvements in global health and prosperity over the last hundred years, but many have been left behind, the former President said.

“While globalization and technology have opened up new opportunities, have driven remarkable economic growth in previously struggling parts of the world, globalization has also upended the agricultural and manufacturing sectors in many countries. It’s also greatly reduced the demand for certain workers, has helped weaken unions and labor’s bargaining power,” Obama said.

“And the result of all these trends has been an explosion in economic inequality. It’s meant that a few dozen individuals control the same amount of wealth as the poorest half of humanity. That’s not an exaggeration, that’s a statistic,” he said.

Indeed, 42 people have the same amount of wealth as the poorest half of the world, according to a study released in January by the global charity Oxfam. And 82 percent of the money made in 2017 went to the wealthiest 1 percent of the global population, the report says.

Billionaire investor and Berkshire Hathaway CEO Warren Buffett has given billions of dollars worth of stock to charity in annual gifts each year since 2006. On Monday, Buffett donated approximately $3.4 billion worth of shares to five prominent charities, including the Bill and Melinda Gates foundation.

This year, an unlikely organization also landed a donation from the Oracle of Omaha: a student-run newspaper at the University of Nebraska.

The Daily Nebraskan Editorial Support Fund received 524 shares of class B common stock in Berkshire Hathaway on July 16, according to the company's SEC filings. Based on Monday's closing price of $192 per share, that donation totals $100,608.

Buffett made the donation as part of a fundraising campaign started by the newspaper in January, Daily Nebraskan General Manager Dan Shattil tells CNBC Make It.

Funding to pay the paper's staff of 150 student reporters and editors has typically come from a mix of fees the university collects from students, and self-generated funds through advertising. But, lately, it's grown more difficult to bring in revenue, a debacle many digital media enterprises are facing.

So the student outlet decided to seek donations and set up a fund, to be invested through the University of Nebraska Foundation, in order to finance the senior editorial staff's wages in perpetuity.

"We created this fund to basically guarantee The Daily Nebraskan will always exist, will always have at least a senior staff in place," Shattil says.

While no one can definitively say where the next financial bubble will occur, Nobel Prize-winning economist Richard Thaler says he's avoiding making this particular investment: bitcoin.

Thaler, known as the "father of behavioral economics,” is a vocal skeptic of bitcoin as a currency. In a new episode of the Freakonomics Radio podcast, Thaler tells host Stephen Dubner that when it comes to investing, he follows billionaire investing mogul Warren Buffett’s simple advice.

"Warren Buffett says a lot of smart things, and one of the things he says is, don’t make investments in things you don’t understand," Thaler says. "And I have no clue [when it comes to bitcoin].”

Bitcoin is just one of many forms of cryptocurrencies that are used as digital currency and are accepted by a select amount of businesses and merchants, but is not considered legal tender in the U.S. Bitcoin is also currently the world’s most valuable virtual currency by market value, trading at more than $6,700, according to industry website CoinDesk, which tracks prices from several exchanges.

While Warren Buffett’s business partner and right-hand man Charlie Munger is worth an estimated $1.7 billion, he has also made his fair share of mistakes. But Munger argues that failing is a sign that you’re doing something right.

When a shareholder asked the Berkshire Hathaway vice chairman about how to recover from a big missed opportunity during an annual meeting of the Wesco Financial Corporation, Munger quoted the late Nobel Prize-winning poet Rudyard Kipling. “You know what Kipling said? Treat those two impostors just the same — success and failure,” Munger said, paraphrasing a line from the poem “If.”

“Of course, there's going to be some failure in making the correct decisions. Nobody bats a thousand,” Munger said. “I think it's important to review your past stupidities so you are less likely to repeat them, but I'm not gnashing my teeth over it or suffering or enduring it.”

“I think the tragedy in life is to be so timid that you don't play hard enough so you have some reverses,” he added.

Warren Buffett's annual donation of stock to five foundations is worth around $3.4 billion this year.

In a news release, Berkshire Hathaway said Buffett converted 11,867 of his Class A shares into around 17.8 million Class B shares to make the contributions.

Based on the schedule established in 2006, when Buffett pledged to give away the bulk of his fortune in the coming decades, the Bill and Melinda Gates Foundation will be getting a large majority of the shares.

At Monday's closing price of $192, the 13.5 million shares going to the Gates Foundation are worth around $2.6 billion.

While the number of shares donated declines each year, a 12.8 percent increase in price of Class B shares from last year's $170.25 means the the value of the gift will have increased by about 7.1 percent from $2.42 billion.

Including this year, Buffett will have donated 243.3 million Class B shares to the Gates Foundation, just under 49 percent of the 500 million shares pledged. Next year's gift will bring the total percentage to 51 percent.

The total value of the gifts, using the market price at the time of the gifts, will be $24.5 billion, an average of $100.61 per share.

The total value using the current stock price would be $46.7 billion.

Along with the Gates Foundation, four family foundations are also receiving stock: the Susan Thompson Buffett Foundation, Sherwood Foundation, Howard G. Buffett Foundation and NoVo Foundation.

Berkshire said that including this year's gifts, the five foundations have received about 43 percent of Buffett's 2006 holdings with a market value of about $31 billion at the time of the contributions.

At the 2007 Berkshire shareholder meeting, Buffett explained why he decided to "farm out" his philanthropy by donating to foundations run by family members and his friend Bill Gates.

"When I have money to give away, I believe in turning it over to people who are ... energized, working hard at it, smart ... doing it with their own money, the whole thing. And I get to keep doing what I like doing. So as far as I’m concerned, I haven’t given away a penny."

For the 81 years Piccolo Pete's Italian steakhouse was open in Omaha, Nebraska, it was a neighborhood restaurant where families came to eat heaps of pasta with red sauce and 16-oz. T-bone steaks, served by a staff of locals. Above the tables in the wood-paneled dining room, a sparkly crystal ball hung as a relic from the restaurant's days of hosting ballroom dancing with dinner.

Then, in 2005, something quite exciting happened at the family-run eatery: A billionaire came to dinner.

A very important customer

Warren Buffett, "the oracle of Omaha," first started frequenting Piccolo's in May of 2005, according to the restaurant's former general manager, Scott Sheehan. That winter, he decided to have his company Christmas luncheon at the restaurant.

Waitress Ellen Augustine, 43, remembers arriving for her shift on that afternoon in the winter of 2005 — she could sense excitement in the air. "I can't lie, I was a little bit nervous," she tells CNBC Make It. She kept telling herself "He's just a human."

Today, at 87, Omaha native Buffett is one of the wealthiest people in the world, worth over $82 billion. His financial conglomerate Berkshire Hathaway has a market cap of more than $472 billion. In 2005, Buffett was already worth a fortune — and important to woo as a diner.

Buffett's event was a big deal for the restaurant (in addition to the obvious reasons) because back then he was known to be a loyal diner at rival Omaha steakhouse Gorat's, Augustine explains. Now, he was coming to Piccolo's, and the owners had high hopes he'd become a regular.

Both Berkshire Hathaway CEO Warren Buffett and business mogul Kim Kardashian West are wildly successful in their own spheres. But the pair have another thing in common as well: They agree that the best investment they’ve ever made is in themselves.

"Ultimately, there's one investment that supersedes all others: Invest in yourself," Buffett told Forbes. “Address whatever you feel your weaknesses are, and do it now.”

The legendary investor learned this lesson firsthand when he enrolled in a $100 public speaking course as a young adult, which he says changed his life. The course was taught by Dale Carnegie, the well-known author of “How to Win Friends and Influence People.”

"I was terrified of public speaking when I was young. I couldn't do it," Buffett says. He admits he became physically ill when the time came to take the podium. Still, he was determined to complete the course and master his fear. Not only did that make him a better investor and salesman, but he says he gained so much confidence that he proposed to his wife during the course.

Amazon boss Jeff Bezos is now $50 billion richer than any other person alive.

Bezos is currently worth $143.3 billion, according to Forbes, which is just over $50 billion more than the next richest person alive, Microsoft co-founder Bill Gates, who is currently worth over $93 billion.

In the context of other billionaires, that $50 billion difference is nearly equal to Google co-founder Sergey Brin's entire fortune (currently $52 billion) or 13.5 times Mark Cuban's net worth (currently $3.7 billion, according to Forbes).

Bezos’ wealth has been climbing as shares of Amazon have been skyrocketing. A year ago, shares of Amazon were hovering at about $1000 per share. Today, they are trading at more than $1750 per share.

Bezos was born the son of a teen mom, was valedictorian of his high school class, went to Princeton and started a career in finance in New York City. But at age 30, Bezos walked away from his job to launch Amazon. "After much consideration, I took the less safe path to follow my passion, and I'm proud of that choice," the entrepreneur says in his 2010 graduation speech at Princeton.

Bezos is also the founder of aerospace company Blue Origin, into which he plans to invest much of his Amazon money.

According to self-made millionaire Timothy Kim, you don't need to be intelligent in order to be wealthy. Instead, he says you just need to learn what highly successful people did to become rich and copy them.

"I'm not that smart, I was an average student and I probably have ADD," Kim tells CNBC Make It. "I just found the right people who've already done it and I just follow what they do."

Kim, 31, officially became a millionaire last year and was featured by Business Insider in November. Now with a net worth of $1.32 million, he runs the personal finance blog TubofCash.com where he hosts cash giveaways.

The millionaire investor attributes his rapid success to heeding the advice of highly successful people. In fact, he may not be a millionaire today if he hadn't followed the advice of a former professor while studying as an undergraduate at Biola University.

Kim says that his college business professor had become wealthy after making several successful investments in the stock market. One morning, the professor nonchalantly told the class that he had just lost $60,000 on a bad stock. However, he encouraged a then 19-year-old Kim and his fellow classmates to immediately invest and to "go in on the market."