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 Fifth Third Bancorp jumped 59% when results of the government's stress tests revealed that less capital needed to be raised than many had expected.          

But beyond less-predictable events like that one 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 130,000 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 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 may change as the market does.

Company

CAPS Rating
(out of 5)

4-Week
Price Change

Northgate Minerals

*****

31.6%

Brocade Communications Systems (NASDAQ:BRCD)

****

28.6%

STEC (NASDAQ:STEC)

***

74.7 %

GMX Resources

***

70.1 %

Conseco (NYSE:CNO)

***

53.0 %

Source: Motley Fool CAPS. Price return from April 17 through May 15.

Brocade Communications Systems
Brocade took a big risk in acquiring Foundry Networks last year, but the deal looks to be paying off now that the company has expanded its relationship with IBM (NYSE:IBM) to sell some of Foundry's routers and switches. Brocade has had a long-standing relationship with IBM, which already sells some Brocade equipment, which mostly consists of storage area networking products.

But IBM has grown more interested in gaining share on the home turf of networking rival Cisco (NASDAQ:CSCO) lately, which is all good in Brocade's eyes.

Slapping the IBM brand on Brocade's Ethernet switching and routing products and moving the products through its sales channels have got investors excited enough to move the stock up almost 30% and out of penny-stock land lately. While many investors have long written off the dot-com darling, some investors have been surprised to rediscover some real potential in Brocade, especially since the Foundry Networks acquisition.

And with partner IBM showing continued strength amid a weak market, it's not too surprising that 94% of the 545 CAPS members rating Brocade expect it to outperform the market.

STEC
Higher shipments for STEC's solid state drives (SSDs) helped boost its first-quarter net sales by 25%, with earnings growing 61%. But the company wasn't content with simply giving investors solid numbers in the recent quarter, so it also bumped up sales forecast for its ZeusIOPS SSD to $65 million, from $53 million, for the first half of 2009. IBM has also been keen on STEC's solid state drive solutions, enough in fact to include them in many enterprise storage products -- a move that could spur even wider use of the technology.

A growing list of companies like SanDisk (NASDAQ:SNDK) and Seagate Technology see potential in SSDs, too, and competition could certainly increase in the growing market. But STEC and some CAPS members think the company has a good lead with a very strong position in the enterprise SSD market and a line of SSDs used in servers made by tier-one customers like EMC (NYSE:EMC) and Sun Microsystems.

This Fool sees more growth potential for STEC as the demand for SSDs grow, and at today's prices nearly 90% of the 364 CAPS members rating the company expect it to beat 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 5,300 stocks that our 130,000-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 experts at Motley Fool Stock Advisor scour the market for top stocks poised to beat the market over the long haul. To see all the stocks that have helped Tom and David Gardner beat the market by 40 points on average, 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 no shares of companies mentioned here. The Fool's disclosure policy has the momentum of a freight train, but can stop on a dime.