Some stocks are one-hit wonders, making a big splash when they first appear, then quickly fizzling into obscurity or oblivion. But for other stocks, that initial big move is only a preview of even bigger and better gains.

Today, we've listed three stocks that made some of the biggest moves up over the past 30 days, which we'll pair with the ratings issued by our Motley Fool CAPS community. The higher each stock's rating, the greater CAPS members' faith in that company's ability to keep on beating the market.

Stock

30-Day  % Change

CAPS Rating
(out of 5)

Ambac Financial (NYSE: ABK)

246.2%

*

ArQule (Nasdaq: ARQL)

94.7%

*

Central Pacific Financial (NYSE: CPF)

81.9%

*

30-day change from March 26 to April 26.

As the markets whipsaw to changes in consumer sentiment, there will be weeks like this one when we see gains that are exceptionally ahead of the pace of the movers and shakers of previous weeks. So before we get shaken out again, let's see why the CAPS community thinks some of these companies might continue to outperform the market.

A mighty temblor
If we need any further confirmation that this stock market rally is based on everything but fundamentals, look no further than the rising stock price of bond insurer Ambac Financial.

The jump was fueled in part by quarterly results showing it had earned a profit, but that was largely on the basis of a change in tax law allowing the company to carry back operating losses in 2008 and 2009 as far back as 2003. The resulting $472 million tax break shows there is no real safety net below, and while Jim Cramer suggests you should buy into what he calls this "worthless" stock's rally, investors would be better off noting Ambac could wind up in bankruptcy protection.

Ambac and MBIA (NYSE: MBI) -- whose stock is up 79% over the same period -- were crushed by the implosion of the financial markets and having to pay billions to companies that had bought bond insurance. With regulators in Wisconsin seizing Ambac's main insurance business, analysts conclude that this is a de facto default by the bond insurer and is an action that sets it up for a legal showdown, because the move apparently leads to one group of policyholders being treated better than others.

Ambac is well off its recent high of $3.39 a share, no doubt as traders took some quick profits. CAPS member SouthHavenSal realizes there was no fundamental basis for Ambac's recent rise and is looking for a collapse.

[While] ABK has made a [substantial] run in the past two trading days, the fact of the matter is that the business has not materially changed and will be filing for Bankruptcy in 2010 or early 2011. While the 2009 Q4 earnings were positive, there were based on a non-operating activity (carry forward of losses for tax purposes). No other fundamentals have changed and the company is not generating any new sources of revenues.

Still feeling the aftershocks
Apparently the stigma that used to attach to a reverse split doesn't apply anymore. While companies in financial trouble still use the maneuver to artificially inflate their share price, if only to maintain a stock exchange listing, a number of other companies have used it for other purposes. Biglari Holdings (NYSE: BH) initiated a 1-for-20 split to shake loose smaller shareholders, and Coeur D'Alene Mines (NYSE: CDE) found it wasn't fatal to implement a 1-for-10 reverse split.

Yet just because more financially sound companies are engaging in the tactic doesn't mean that when Hawaii-based Central Pacific Financial asks shareholders to approve a reverse split as large as 1 for 20, it should be seen in the same light. Central Pacific Financial is facing serious credit stress, and Fitch Ratings warned that it is possible that regulators could seize the bank. That's probably why CAPS All-Star tenmiles says the bank will likely need to be on life support soon.

And thereby hangs a tale
At least ArQule's jump was a result of a positive development for its lung cancer therapy, for which trials showed patients living longer without their disease progressing. ArQule is testing its treatment by pairing it with Tarceva -- a drug sold by Roche and OSI Pharmaceuticals (Nasdaq: OSIP) -- and the results should warrant its progress into phase 3 trials, but there are a lot of companies pairing their formulations with Tarceva or targeting the same market.

CAPS All-Star and biotech guru zzlangerhans says the market has overreacted to the news.

For those of you who missed it, ArQule reported that adding ARQ197 to Tarceva appeared to improve progression-free survival to 16 weeks, vs 9 weeks for Tarceva controls. So, horrible survival numbers could potentially be improved to slightly less horrible survival numbers.

Head over to the ArQule CAPS page and add your thoughts on the biotech.

Shake, rattle, and roll
With these stocks shaking the market, it pays to start your own research on them at Motley Fool CAPS. Read a company's financial reports, scrutinize key data and charts, and examine the comments your fellow investors have made -- all from a stock's CAPS page.