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, shares in Terra Industries recently rose 25% when CF Industries offered about $2 billion in an all-stock buyout of the company.

But beyond less-predictable events like that, many stocks have fundamentally compelling reasons for their 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 125,000 CAPS members to filter out the noise and find companies offering strong momentum.

We've used CAPS' handy stock screening tool to quickly zero in on companies with a stock price increase of at least 25% in the past four weeks, a market cap of greater than $100 million, and a beta of less than 3.

Below is a sample of stocks that our screen returned. If you'd like, run this screen yourself; just keep in mind that results will be updated as the market changes.

Company

CAPS Rating
(5 stars max.)

4-Week
Price Change

SanDisk (NASDAQ:SNDK)

****

28.0%

Research In Motion (NASDAQ:RIMM)

***

28.9%

Whole Foods Market (NASDAQ:WFMI)

***

27.9%

Source: Motley Fool CAPS. Price return from Dec. 26 through Jan. 23.

Good memories
After falling through much of 2008, SanDisk shares broke below $10 a stub following its rebuff of Samsung's offer to purchase the company back in September. The flash memory industry has been brutal lately, since it has been faced with excess supply as demand for consumer gadgets has dropped due to the poor economic outlook.

But investors have shown a renewed interest in SanDisk stock, with its unveiling of new products at the Consumer Electronics Show early in January. Its portable music products are No. 2 behind Apple (NYSE:AAPL) but hold a strong position ahead of other competitors such as Microsoft's (NYSE:MSFT) struggling Zune player. SanDisk announced its new Sansa slotRadio music player, which will begin selling in early 2009, in hopes of capturing users who would rather have preloaded music on removable memory cards rather than loading an iPod themselves.

It also made a splash with some new high-capacity memory drives for computers. SanDisk recently unveiled the world's fastest series of solid state drives (SSDs), which are up to five times faster than some traditional hard drives and could render them obsolete. SSDs are finding their way into more laptops, replacing traditional hard drives from makers such as Seagate (NYSE:STX).. By upgrading older laptops to the faster solid state drives, companies could be able to delay larger capital expenses of new equipment purchases. Considering the lower share price and new prospects for growth, 93% of the 1,690 CAPS members rating SanDisk expect it to outperform the market.

Smarter than the average phone
Analysts are still grappling with a prognosis for BlackBerry-maker Research In Motion (RIM). As the smartphone market has cooled down, consumer business will certainly slow and tight corporate spending could potentially affect sales of the BlackBerry as well.

But RIM is showing resilience. Research firm Canaccord Adams recently estimated that RIM's BlackBerry phones outsold Apple's iPhones in the smartphone market in the fourth quarter, and that Apple's win over RIM in the third quarter was a one-time occurrence. Many investors believe RIM may hold up better than others in a slower smartphone market as well. No. 1 seller Nokia (NYSE:NOK) is losing share in the global market as it recently reported falling quarterly profits.

Motorola isn't doing any better, and recently announced another round of layoffs in an attempt to regain some of its former glory. Even with the bleak outlook in the consumer and corporate environment, 83% of the 4,832 CAPS members rating Research In Motion remain bullish.

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 nearly 5,400 stocks that our 125,000-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 Inside Value service looks for solid companies with shares beaten down to dirt cheap levels. To see what companies the analyst team believes are priced way below intrinsic value today, take a free 30-day trial.

Fool contributor Dave Mock has his own story, but there's no "happily ever after" at the end of it. He owns shares of Motorola. Nokia and Microsoft are Inside Value recommendations. Whole Foods Market and Apple are Stock Advisor picks. The Fool's disclosure policy has the momentum of a freight train, but can stop on a dime.