Even on the market's worst days, buyout news and other short-term forces can send individual stocks up by 10%, 25%, even 50%.               

For example, when the Dow Jones Industrial Average had its best point gain ever of 936 points last Monday, oil mammoth ExxonMobil (NYSE:XOM) surged 12%, and Morgan Stanley partied its way to an 87% increase.

But beyond less-predictable events and market bounces are stocks with fundamentally compelling reasons for recent momentum. The trick is to find those stocks. That's where Motley Fool CAPS comes in.

The story behind the story
CAPS is no crowd of lemmings. Its best-performing members' opinions do more to shape each company's rating than the picks of their poorer-performing peers. Let's use the collective wisdom of more than 120,000 CAPS members to filter out the noise and find companies offering strong momentum.

We'll use CAPS' handy stock screening tool to quickly zero in on companies with a stock price increase of at least 15% in the past 13 weeks, a market cap of greater than $100 million, and a beta of less than 3.

Here's a sample of the stocks our CAPS screen returned:

Company

CAPS Rating
(out of 5)

13-Week
Price Change

ViroPharma (NASDAQ:VPHM)

*****

15.0%

Shanda Interactive (NASDAQ:SNDA)

*****

15.0%

Buffalo Wild Wings

****

23.5%

Source: Motley Fool CAPS. Price return from July 18 through Oct. 17.

Cash is king
Recessions, depressions, and times of panic tend to turn investors toward "defensive" industries -- those that remain somewhat stable despite poor economic conditions. Lately, many investors have turned to health-care and big pharma companies like Pfizer (NYSE:PFE), Johnson & Johnson (NYSE:JNJ), or Merck (NYSE:MRK) that provide safety with the immense piles of cash on their balance sheets. Antibiotic drugmaker ViroPharma has similarly earned high favor in CAPS for its pile of cash and strong balance sheet as well as its big future potential.

Its current drug, Vancocin, hit a single quarter net sales record of $65.4 million in the second quarter, and the company increased 2008 sales guidance for the drug to between $220 million and $240 million. Many investors think that alone makes ViroPharma a compelling value, but the company also expects to pick up orphan drug Cinryze in its $442 million acquisition of Lev Pharmaceuticals and predicts the potential for $250 million to $350 million in peak annual sales for the drug. 

Cinryze was recently approved by the FDA to treat a rare disease called hereditary angioedema, or HAE, and is expected to be available to patients later this year. It’s the first HAE treatment in the U.S. and should bring in strong profits as each dose could cost several thousand dollars.

CAPS members had ViroPharma rated as a five-star stock at the start of the year, and the stock has performed well. Despite more than a 50% gain year to date, more than 97% of the 1,134 CAPS members rating ViroPharma remain bullish and expect it to outperform the market going forward.

Game on!
It's hard to argue against the immense opportunity tied to the Internet in China. With more than 250 million Chinese already online -- and about another billion left to tap -- Baidu.com (NASDAQ:BIDU) is helping lay the foundation of a bright future for several online companies, including online entertainment firm Shanda Interactive.

CAPS members like Shanda's prospects in the growing online gaming niche as China’s middle class grows. The company's capital-light business structure gives it the ability to earn large returns on its invested capital, which its management has a solid history of producing. The company also consistently produces in other ways -- Shanda has beat profit expectations for nine consecutive quarters. In the latest quarter, the company blew away expectations and reported profits of $0.56 per share when Wall Street was looking for just $0.51 a share.

The company recently closed on its sale of $175 million of convertible senior notes, which it plans to use to buy back as much as $175 million of its stock. A large group of CAPS members see value in the stock as well, as more than 97% of the 849 members rating Shanda Interactive see it beating the market.

And you?
What's your story? Whether you buy the tale of a stock that's soaring or souring, your own research is more important than collective opinions. But these collective opinions can make your due diligence a whole lot easier.

Add your take on these or any of the 5,400 stocks that our 120,000-plus members have covered in Motley Fool CAPS. It's totally free to be a part of the community, and the payback is more than worth it.

The Motley Fool Hidden Gems service looks for companies like Buffalo Wild Wings with exceptional management and growth prospects. Check out what other gems lead analysts Tom Gardner and Bill Mann are recommending today with a free 30-day trial to the service.

Fool contributor Dave Mock has his own story, but there's no "happily ever after" at the end of it. He owns shares of Pfizer, Johnson & Johnson, and ExxonMobil. Buffalo Wild Wings is a Hidden Gems pick. Pfizer and Johnson & Johnson are Income Investor selections. Pfizer is an Inside Value pick. Shanda and Baidu are Rule Breakers selections. The Fool owns shares of Pfizer and Buffalo Wild Wings. The Fool's disclosure policy has the momentum of a freight train but can stop on a dime.