Chances are you've never heard of Larry Ellison, but you might be using products made by his company this very moment. You see, Larry Ellison is the CEO of software giant Oracle (NASDAQ: ORCL), making him the fifth richest man in the world, and third richest American.

Ellison is known for his brash, proud personality. From a 1996 appearance on Oprah as America's most eligible bachelor to making headlines for his wildly extravagant purchases, he's certainly hard to ignore.

With that in mind, here are seven of the quirkiest stories surrounding the unforgettable Larry Ellison.

1. Your Redwoods Will Not Stand In His Way.

Ellison is a man who aims to be the best -- and to see the best. So when a neighbor's redwood trees grew tall enough to obstruct his view of the San Francisco Bay, he took a two-prong approach. First, he asked them to cut down the offensive tree. When they refused, he took the bull by its horns and filed a complaint with San Francisco's 'tree dispute reconciliation' system in hopes they would force them to cut down the offending trees.

Apparently that didn't work, but Ellison had a backup plan that only a billionaire could cook up: he bought the home next door for $40 million, ensuring that he would still have a great view of the Bay. His reason for wanting good views of the Bay? The America's Cup yacht races will be held there this year. We'll tell you more about Ellison's passion for yachting in a moment.

2. He Almost Dieed In A Boat Race.

Ellison is a thrill-seeker, and yacht racing is his thrill of choice. In a 1998 Australian boat race, a typhoon struck the area and wreaked mayhem on the racers, killing six sailors from other ships. Ellison and the 24 crewmen on his ship, Sayonara, survived, suffering at worst broken bones, but the experience helped remind him that 'life is glorious and fragile and short.'

3. He'll Tell You How He Feels.

Opening an e-mail entitled, 'Hey Jerk' from a billionaire CEO isn't how most magazine writers want to start their day. But that's exactly what happened to Fortune writer Philip Elmer-DeWitt.

In 2010, Ellison called Elmer-DeWitt a 'scum bag' for referencing a sexual harassment lawsuit brought against him by an employee. (Ellison did win the suit.) The Fortune article compared Oracle to Hewlett Packard (NYSE: HPQ) on, ahem, issues of executives' personal lives after former HP CEO Mark Hurd was fired over sexual harassment allegations and false expense reports. Another Oracle executive had been caught in an affair worthy of its own soap opera, but Ellison didn't fire him. A month after Hurd's ousting from HP, Ellison hired him as the president of Oracle.

4. His Love Of Yachts Has No End.

You might think that a brush with death aboard a catamaran would leave a bad taste in the billionaire's mouth for boats, but Ellison can't get enough. He enjoys watching and participating in boat races and is the owner of a sailboat racing syndicate that won the 2010 America's Cup. The racing team has four boats, including the USA 17, featuring a main sail that is 55 percent larger than an Airbus 380 wing and taller than the Statue of Liberty, making it the largest rigid wing ever.

[Check out this InvestingAnswers feature, '12 Luxuries Only Billionaires Can Afford.']

His first yacht, Rising Sun, was built to surpass the size of Paul Allen's yacht and reportedly cost more than $200 million. He later sold the yacht to David Geffen. However, he just took delivery of a new ship, the samurai-themed Musashi, a much smaller 288-foot ship. Apparently, the other was just too big. For once, Ellison decided to downsize.

5. He Dreams Of Ninja Stardom.

His large new ship, Musashi, doesn't just have a samurai theme; it is named after the most famous samurai ever. His $200 million mansion in Woodside, California is designed to look like a 16th century Emperor’s palace, and filled with his collection of samurai armor. Perhaps, he was born in the wrong time and place, but a billionaire software tycoon isn't too shabby.

6. He Rescinded A Gift Of $115 million To Harvard.

If you've ever had a rich aunt promise you a nice gift only to never deliver, you can understand a small taste of what Harvard University felt in 2005. Ellison promised the already well-funded university their largest single gift to date: $115 million, a staggering sum for any university. However, when Ellison's buddy Larry Summers stepped down after a controversial tenure at the University, Ellison backed out of his promise.

7. He Invested Big Bucks In Fancy Dumpster Diving.

When Ellison felt that Microsoft's (NASDAQ: MSFT) database software products were threatening Oracle's edge, he first went to the government to complain of antitrust violations. Then he went rogue. Oracle hired the hardcore dirt detective firm, Investigative Group International (whose list of clients includes the tobacco industry and Bill Clinton) to find financial ties between Microsoft and supporters.

In the course of the work, investigators used such highbrow methods as digging through the trash to, according to Ellison, 'take information that was hidden and bring it to the light.'

The Investing Answer: Money can't buy happiness, but it can buy material objects that satisfy your passions. Many of the world's richest people have eccentric personalities, but that's often how they've risen to the top. If you want to learn how to think like a billionaire, check out '3 Billionaire Habits for Non-Billionaires.'