Motley Fool co-founder David Gardner thinks he can pick stocks. He thinks he can do it better than his brother Tom.

He thinks he can do it even better than you.

From 1993 to 2003, David's Rule Breaker portfolio returned better than 20% annualized, a clip that far outpaced the broader market. Tom's picks in Motley Fool Hidden Gems are up 24% on average, better than the S&P 500's 13%.

Since 2003, David and Tom have recommended dozens of stocks to their Motley FoolStock Advisor subscribers. Tom's picks are up 73% on average, better than David's 52%.

And here's what we know about you .
Nothing! Sure, you talk a good game, and you seem nice enough. And like everybody I pass on the street, you seem to have bought a lot of great stocks in your time. An awful lot of great stocks, come to think of it.

You found Microsoft (NASDAQ:MSFT) in 1986 and Dell (NASDAQ:DELL) in 1990, and both yielded annual returns of more than 30% during their respective runs. But you were just getting warmed up. You nabbed Cisco (NASDAQ:CSCO) in 1991 for a split-adjusted price of less than a buck, and you cashed out at $82, near the top in March 2000. Right? Hey, I'm just saying.

Come to think of it, I'm not just saying. I'm implying. I might even be insinuating. If my name were Thomas, I'd be doubting. And so would you, if everybody you met claimed he or she knew that Intel (NASDAQ:INTC) would move a gazillion chips or that folks would line up to pay Starbucks (NASDAQ:SBUX) three bucks, for Pete's sake, for a cup of coffee.

Whew, I'm glad I got that off my chest!
You know there's a grain of truth in what I say. You know how much better your "hypothetical" results tend to be than your "actual" results. Especially if you're an optimist like I am and you tend to remember the winners and sweep the losers under the rug.

Of course, there's one thing that never lies. And that's your monthly brokerage statement. But buying and selling real stocks can be an expensive way to prove your prowess -- much less to test out some new hypothesis or technique.

But are you really willing to share your personal financial information with a chump like me? Fat chance. However, what if there was another way? What if there was some sort of tool that allowed you to make virtual buys and sells, compete with thousands of other investors, and track your results in real time for the world to see? Sound interesting? Sound scary? Darn right it does.

But what it doesn't sound is lonely
Isn't that the problem with model portfolios, after all? You know, like the ones you load into financial websites, such as the one at Yahoo! -- they're handy and easy to check, but they're just so ... well, lonely. Plus, it seems a little pretentious on an up day to email the link to your friends. (Yes, I've done it.)

This probably has little to do with why a team of webheads at The Motley Fool spent two years developing a new site they're calling CAPS. To hear it from them, the real goal was to develop a robust database of community intelligence that you can use to find better stocks.

I have my own theory on community intelligence, which we can discuss at length later. But I love to compete, and I love stocks. I even love to be held accountable. Nothing pains me more than not being able to brag about how I bought in on the Google (NASDAQ:GOOG) IPO a couple of years ago and shorted the heck out of Lucent (NYSE:LU) at the top ... becausenobody would believe me. I'm sure you feel the same way.

So put your mouth where your money is
If you want to check out Motley Fool CAPS, that new beta research tool I'm talking about, here's a link. (You'll have another opportunity just ahead.) It's free to use, and you won't be asked for anything beyond maybe an email address. Then you simply "rate" at least seven stocks -- any seven you like (or hate) -- and you're off to the races.

While you're at it, you can check out the top-ranked players, the top-ranked stocks, and the portfolios of some experts you may recognize. But more importantly, you'll be in the mix. Your pals can see your picks, and you can see theirs. The clock will be ticking on your portfolio, and you'll be on your way to being ranked yourself.

But be warned: Being ranked is a double-edged sword. I entered my own model portfolio about a week ago, and let's just say I'm in it for the long term. Seriously, I check my brokerage account (and now my CAPS account) no fewer than 10 times a day. I'm a stock guy, but I am also a long-term investor. And I hope you are, too.

Think you can beat David Gardner?
Or how about Tom? Both brothers have portfolios in the CAPS platform. Or maybe Jim Cramer? He's not actually playing yet, but the folks at the Fool are tracking his public picks to see how they hold up.

Or how about Charly Travers? Charly is a CAPS "All-Star." That means his player rating is 80 or higher. That rating places him squarely in the top 20% of the thousands of investors who have logged on to CAPS so far.

In fact, when I started this column, Charly was the top-rated player. Already, he's been knocked down a few notches. Now that's what I call accountability. There really is nowhere to hide. Considering how far behind I am already, I give myself one year to knock him out. But you can start with a clean slate today.

The future of investing?
Eventually, CAPS may be a valuable stock-research tool for millions of investors worldwide. Who knows? Maybe it will become like online trades and real-time streaming quotes -- indispensable for serious investors. But that's some time away.

For right now, it's a killer competition and a lot of fun. So if you like to compete and you like stocks ... and if you don't mind the whole world seeing how you stack up, you might want to check it out. I've been "all in" for about a week, and so far, it's a blast.

And remember, the whole thing is free. Simply head over right now and rate seven stocks. Check out CAPS for yourself.

Paul Elliott doesn't own any of the stocks mentioned. Microsoft and Dell are selections of the Inside Value newsletter service. Starbucks and Dell are Stock Advisor recommendations. The Motley Fool has a disclosure policy .