If you think what I’m about to tell you sounds too good to be true, I don't blame you. I was a skeptic, too.

And I've been at this awhile. Including five years holed up with a "quant" whacko who couldn't flip a sofa cushion without finding "alpha." I know what you're thinking ...

What the heck is alpha?
Without digging myself too deep a hole, "alpha" is the excess return you're earning on your stock portfolio, beyond what some academic would predict given its level of risk. Put another way, alpha is the measure of your ability to pick better stocks than I can.

This much I know for sure: Alpha is the driving force behind a trillion-dollar hedge-fund industry. Kind of remarkable, since I remember paying roughly that much for some wise guy to teach me that alpha doesn't exist.

And that's what I believed. Sure, I'd seen investors beat the market. Then I'd seen them get crushed. Chet Hammersmith would get a hot hand loading us up on Cisco (NASDAQ:CSCO) and Sun Microsystems (NASDAQ:JAVA) in 1995 -- and then we’d get our heads handed to us in 2001. And so it goes in an “efficient” market.

Now it gets good ...
So when my friend and colleague David Gardner started telling me he'd captured alpha -- and that he'd hired a NASA scientist to prove it -- I barely gave it a second thought. True, this was the guy who told me to buy Amazon.com back in 1997, before it went on a 2,800% run.

Not to mention Amgen in 1998 and AOL in 1994, the latter at $0.43 a share. The guy has a nice touch, but that's a far cry from true, positive alpha. And remember, I barely believed that alpha even existed.

That's where the NASA guy comes in. First, he used his big brain to randomly generate 25,000 hypothetical stock portfolios. Next, he created a portfolio of his own, using Gardner's proprietary, so-called alpha-generating model. Turns out the NASA guy's portfolio outperformed 99.4% of the random portfolios.

Wait until you hear how he did it
Amazingly, that experiment isn't what changed my mind. Before I tell you what did make me a buyer, you must be wondering what David Gardner is feeding into his supercomputer. Oddly enough, it's you. Seriously.

You see, Gardner has long argued that many smart, ordinary investors will always be smarter than any one "expert." He's been proving this theory in an ad-hoc fashion for years. This "community intelligence" supported his belief in China Internet provider Baidu (NASDAQ:BIDU) back in November 2006 -- the stock’s up 239% since.

He tapped into it again when he recommended that we buy NVIDIA (NASDAQ:NVDA) in May 2005, and Marvel Entertainment (NYSE:MVL) as it emerged from reorganization in 2002. That pick's still up more than 900%. According to David, he's now found a way to collect his community intelligence on a mass scale and "quantify" it.

In other words, he's transformed a disparate bunch of opinions, insights, and bits of knowledge from something he could vaguely process in his own head into something a guy from NASA could stuff into a model.

The experiment that changed things
We discussed how Gardner's "NASA portfolio" outperformed 99.4% of 25,000 random stock portfolios. But if you're like me, that sounds like a lot of big numbers. Here's a second experiment that convinced me that these guys might really be on to something.

This time, they applied their model to a handful of real-life portfolios -- namely, the stocks recommended in The Motley Fool's newsletter services. I like this approach for two reasons. First, these are real stocks, handpicked by real advisors in real time. Second, the guys who assembled these portfolios are legit.

Across six different advisory services -- recommending stocks as diverse as Intel (NASDAQ:INTC) and Pfizer (NYSE:PFE) -- the results were striking. Gardner's "community intelligence" filter cut the number of picks nearly in half, and increased the returns by a stunning 19 percentage points per pick.

Fewer picks, higher returns
So if you ever wondered how a NASA scientist would use your own intelligence to help you beat the market in theory, there you have it. Now I'll tell you a cumbersome way you can use alpha in your own portfolio -- and then I'll show you how David Gardner proposes to do it on a grander scale.

If you own a mutual fund, try this. Cross-reference your fund's alpha with its managerial tenure. (Morningstar's "Risk Measures" tab is a good place to start.) If you find high positive alpha (the higher, the better) and your manager's been at it five years or more, you may have found one of the few gems in the mutual fund world.

Now for the fun stuff: As you probably know, David Gardner's been collecting data from more than 125,000 visitors to our Motley Fool CAPS website. Over the past year or so, he assembled a team, including the NASA scientist I mentioned earlier, to help him analyze and back-test that data to consistently generate positive "alpha."

And he's done it!
Or so he tells me. Gardner insists he has tapped the collective intelligence of the world's smartest investors -- and more important, he can use this data to help us make money in our own portfolios. Sounds crazy, but here's how he plans to do it.

Along with longtime Fool analyst Jeff Fischer, Gardner is investing $1 million of The Motley Fool's money in a long/short portfolio of stocks, options, and exchange-traded funds. They aim to prove that they can combine their community-intelligence data and portfolio-management skills to grow that $1 million investment -- no matter what the market throws our way.

Why should you care? Well, here's the thing. Starting June 16, David will be inviting a small number of Fool readers to follow along with his experiment in real time. In fact, he will announce his portfolio trades in advance -- so that you can buy (or short) ahead of him. But hurry, because the enrollment will be capped and it’s first-come, first served.

If you're as intrigued as I was, check out this message from David Gardner. It could be just the thing you need to get you through this unpredictable market and out the other side with more money than you have right now. To hear it from Gardner, and to receive a private invitation to learn more, simply enter your email address in the box below.

This article was first published Oct. 14, 2008. It has been updated.

Paul Elliott owns shares of Pfizer. Intel and Pfizer are Motley Fool Inside Value selections. Amazon, NVIDIA, and Marvel are Stock Advisor picks. Baidu.com is a Rule Breakers recommendation. The Motley Fool sold puts on Intel and has a disclosure policy.