I am always looking for a good deal, whether that means buying an extra box of Golden Grahams when they're on sale, or pouncing on undervalued stocks. The idea that anybody would sell a stock for less than its worth may seem silly, but legendary value investor Ben Graham (no relation to the cereal) tells us, by way of allegory, how we can look out for these situations.

In The Intelligent Investor, Graham introduces readers to a wacky chap named Mr. Market. Mr. Market's game is to pay you house calls on a daily basis, offering to sell you interests in businesses he owns, or to buy from you interests in businesses you own. Sometimes Mr. Market will show up at your door very excited, offering you premium prices for your holdings; at other times he'll be inconsolably depressed about the future, trying to sell you what he has for as low as pennies on the dollar.

To find some of the stocks that Mr. Market is depressed about, I've turned once again to The Motley Fool's CAPS investor community. Each of the companies below had been given a five-star rating (the highest) by our community of investors just 30 days ago:

Stock

30-day return

One-year return

Current CAPS rating

Hercules Offshore (NASDAQ:HERO)

(57%)

(69.1%)

****

Chesapeake Energy

(49.5%)

(38.2%)

*****

Cemex (NYSE:CX)

(44.8%)

(64.7%)

*****

NVIDIA (NASDAQ:NVDA)

(37.8%)

(80.7%)

****

Transocean (NYSE:RIG)

(34.3%)

(26.8%)

*****

Ingersoll-Rand

(32.3%)

(55.3%)

*****

Noble (NYSE:NE)

(30.4%)

(32.5%)

*****

Data from Motley Fool CAPS as of Oct. 7.

As the table shows, these stocks are all still very well-regarded by the CAPS community despite their underperformance over the past month. While these are not formal recommendations, they could be a great place to kick off some further research. I'll even get you started with some thoughts on Cemex.

Why so blue?
With the S&P 500 off more than 20% over the past month, it's not too shocking that any given stock is down and down big. Take a company like Cemex, which is seen as intimately tied to construction and the housing market, and you'll see investors turn up their noses like they've been served a dinner of boot sole and factory sludge.

The pessimism isn't completely unfounded, though. Just shy of a month ago, Cemex did own up to the fact that its full-year EBITDA would fall short of its original estimates, and that third-quarter EBITDA would be down 3% from 2007.

What the bulls say
As I look around right now, there are a lot of high-quality companies are getting cheaper and cheaper. I'm not the only one who seems to think this -- Warren Buffett has been throwing around big bucks, making major investments in Goldman Sachs (NYSE:GS) and General Electric (NYSE:GE).

Getting back to Cemex, in a market filled with fear over MBSs, CDOs, and any number of other acronyms, we can count on Cemex's business of selling cement and other aggregates to stick around and remain in demand for many years to come. As my fellow Fool David Lee Smith noted last month, Cemex also boasts some great international diversification; along with the solid nature of its business, that global reach should make this stock a solid performer over the long term.

On CAPS, nearly 4,000 members think Cemex's stock will outperform the rest of the market. The humbly named OtherOracleOfOMA is one of these Cemex bulls, recently noting: "Solid company beaten up by the credit crunch, and people will always need cement. I expect the USA to ramp up infrastructure spending after the election as well. All in all, CX is way, way oversold-near its 10-year low."

So do you think the recent drop has created a good buying opportunity? Or is there more pain ahead for Cemex? Let the community know what you think -- head over to CAPS and share your thoughts with the other 115,000-plus players currently part of the community. Even if you'd prefer to pass on Cemex, you can check out a couple of the other stocks listed above or any of the 5,400 stocks that are rated on CAPS.

More CAPS Foolishness:

Cemex is a Motley Fool Global Gains selection. Hercules Offshore is a Motley Fool Hidden Gems pick. Chesapeake Energy is aMotley Fool Inside Value recommendation. NVIDIA and Cemex are Motley Fool Stock Advisor picks. The Fool owns shares of Cemex. Try any of our Foolish newsletters today, free for 30 days.

Fool contributor Matt Koppenheffer does not own shares of any of the companies mentioned. You can check out what Matt likes in CAPS by visiting his CAPS portfolio. The Fool's disclosure policy knows how to drop a stock like it's hot, but only when the company is truly cold.