What's the wealth-making secret of the world's billionaires? For investors on the list, it's sticking to a strategy that plays to their inherent strengths. For many of the others, including five of the top 10, its entrepreneurship.

Oh to be an owner
You know the list: Microsoft's (NASDAQ:MSFT) Bill Gates and Paul Allen, Oracle's Larry Ellison, and Dell's Michael Dell are the four most recognizable names on Forbes' latest list of the nation's richest. Real estate mogul Sheldon Adelson and his $20 billion fortune, comprised mostly of stock in Las Vegas Sands, ranks third and rounds out the list of self-made billionaire entrepreneurs in the top 10.

But there are many more. TD Ameritrade (NASDAQ:AMTD) founder J. Joseph Ricketts ranks 133rd with a $2.3 billion fortune. Meanwhile, Limited Brands' (NYSE:LTD) top fashion cop, Leslie Herbert Wexner, is 83rd with $3.1 billion. EchoStar Communications (NASDAQ:DISH) chief Charlie Ergen ranks 34th with $7.6 billion. And Bernard Marcus, half of Home Depot's (NYSE:HD) founding tandem, is 189th with $1.9 billion.

Invest with owners
If you're feeling envious, I don't blame you. Wouldn't it be great if we were all billionaires, unencumbered by the need for money? Of course it would be. But that's not how the world works.

Still, I find it reassuring that, as rich as Gates and Allen are, the bulk of their wealth came from staying invested in the company that brought them to the billionaires' ball. Why? Because anyone with a brokerage account could have enjoyed similar percentage gains.

In fact, many did. So great is the story of Microsoft's ability to generate wealth that it has a name -- the uprising of the so-called "Microsoft millionaires." At least hundreds of them must still exist. Consider this chart. Every $1,000 invested in Mr. Softy at the dawn of 1990, four years after its debut on the Nasdaq, would be worth roughly $45,000 today.

Searching for the next Microsoft
That's why Motley Fool Hidden Gems co-advisors Tom Gardner and Bill Mann focus on the stocks of up-and-coming firms in which the managers own a significant stake. Some of their best performers still feature meaningful insider ownership.

Consider laser components maker II-VI (NASDAQ:IIVI), which Tom singled out in the August issue for its history of smart acquisitions. The stock is suffering today -- down more than 20% because of disappointing third-quarter results -- but still up more than 60% since joining the Hidden Gems portfolio. That's a boon for the insiders, who still own nearly 20% of the outstanding shares.

So don't envy the billionaire owners. Invest alongside them. They're the ones who really have the best chance to create the next Microsoft, and make you millions in the process. And if you'd like Hidden Gems to help you identify some promising prospects, click here to join the service free for 30 days.

This article was originally published on Oct. 12, 2006. It has been updated.

Fool contributor Tim Beyers owns shares of Oracle. All of his portfolio holdings can be found at Tim's Fool profile. Dell is a selection of the Stock Advisor service. Dell, Home Depot, and Microsoft are Inside Value recommendations. The Motley Fool's disclosure policy always takes ownership.