This article's swaggering headline smacks of exaggeration -- but it's true.

How it happened
Picture it: New Jersey, 1995. Although not then a Motley Fool employee, I was, perhaps like you, an avid reader of Fool.com. Founding Fools David and Tom Gardner occasionally recommended stocks, and one of their recommendations was an online service provider, America Online.

I was still quite new to investing, and I didn't know enough to do much of my own research. But I did have one thing going for me: I was an AOL customer. I used the service every day, and I liked what I saw of its user-friendliness, utility, and potential. So I bought. I snapped up $3,000 worth of shares and hung on.

Over the next several years, the stock went up and down, sometimes significantly -- but I held on. It mostly went up, and it split and split. I remember checking my portfolio regularly -- several times a day! -- to see how rich I was becoming. Near the stock's peak, I had a 70-bagger! My $3,000 investment had turned into $210,000. If it doubled in value only twice more, I'd be (almost) a millionaire! All from a measly $3,000 investment.

Did I sell shares along the ride up? No. (Some of us don't know when to cut our losses.) Did I sell at least some near the top, when my mom told me to? Nope. (That strange thudding sound you hear is me banging my head on my desk. The silence is my mom, biting her tongue.) I held on.

AOL merged with Time Warner in 2001, and for years after that, the stock struggled. I remember when shares were priced in the $70s (that would be north of $200 now, after a recent 1-for-3 reverse stock split), but it's a fuzzy memory. They spent years below $20 ($60, split-adjusted) until relatively recently, and even more recently drifted much lower.

I did sell a big chunk of my shares a few years ago, when I needed money for a down payment on my house. And I finally got smart -- I sold more shares to diversify into other stocks instead of holding a big chunk of my net worth in a company in which I no longer had faith.

I continue to hold a few shares, though, and despite my inclination to curse my stupidity for not selling earlier, I'm still sitting on a handsome profit, even at current levels. My cost basis is ridiculously low, and this has still been one of my best investments ever. I shouldn't complain.

How you can do it
If any part of this story appeals to you, know that you have a chance to make it yours -- perhaps with a happier ending -- if you make a few decisions differently. (You might end up as an accidental billionaire!)

Buy what you know
First, pay attention to products and services you know, use, and love -- especially if you see more and more people using them. There may be a great stock behind them, and knowing their products or services will go a long way toward understanding the business. Plenty of well-known companies have done phenomenally well over the past decade or two -- let's look at a few.

Are you involved in agriculture, aware of new seeds and farming technology introduced by the likes of Monsanto (NYSE: MON)? Do you enjoy playing video games sold by Electronic Arts (Nasdaq: ERTS)? Have you taken any online courses?

Well, Monsanto had a bad 2008, like most companies, but over the past five years (including 2008), it has averaged a 36% annual gain. Over the past decade, Electronic Arts has trounced the market's average return (though not over the past five years), while online education specialist Apollo Group (Nasdaq: APOL) has averaged about 20% annually over the past decade. These companies have performed rather well, right under our noses.

Beware what you don't
Along those same lines, be wary of what you don't understand. If you don't understand how a business makes money, you probably won't be able to tell when business is going badly. If you don't understand the world of offshore contract drilling services for oil and gas wells, then maybe you shouldn't be invested in Transocean (NYSE: RIG).

Level 3 Communications (Nasdaq: LVLT) has been one of the Nasdaq's most actively traded stocks. Do you have a sound understanding of how it makes it money? If not, learn more or steer clear. Continued...