I am always looking for a good deal, whether that means buying extra boxes of Cap'n Crunch when it's 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 tells us, by way of allegory, how we can look out for these situations.

In The Intelligent Investor, Graham introduces readers to a wacky guy who deserves a spot on a cereal box himself. He's Mr. Market, and his game is to pay you house calls every day to try 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 and offer you premium prices for your holdings. Other times he'll be inconsolably depressed about the future and will offer to sell you what he has for pennies on the dollar.

So 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

1-Year Return

Current
CAPS Rating

Nintendo (OTC BB: NTDOY.PK)

(22.7%)

61.1%

*****

Schlumberger (NYSE: SLB)

(21.5%)

19.2%

*****

Ceragon Networks (Nasdaq: CRNT)

(21.5%)

42.5%

*****

Marathon Oil (NYSE: MRO)

(21.1%)

6.0%

*****

Noble Corp. (NYSE: NE)

(20.0%)

17.7%

*****

Baker Hughes (NYSE: BHI)

(18.7%)

(7.4%)

****

Silver Wheaton (NYSE: SLW)

(18.7%)

34.5%

*****

Data from Motley Fool CAPS as of Feb. 5.

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

Shooting fish in a barrel
In a market like this, many stocks have gotten cheaper lately. In fact, for a stock picker, it can be overwhelming to try and figure out where to start!

After a really strong run through 2007, the energy sector has started to see some weakness in 2008, particularly as oil prices have moderated a bit. Underlying issues that have kept the price of oil elevated, however, have not really changed, and we're not likely to see it plummet any time soon.

That said, I'm with fellow Fool David Lee Smith in thinking that oil services companies are more interesting right now, especially as results from producers like Marathon have been less than exciting.

When it comes to oil services, Schlumberger is high on any investor's list. Schlumberger is one of the leaders in the field and provides a range of services from seismic imaging -- through its WesternGeco arm -- to drilling and well completion services. As CAPS player janbcarter pointed out a month ago, "if there's oil there, [Schlumberger] is a factor in getting it out." In other words, Schlumberger is a great way to play the importance of finding new oil without having to determine which company is coming up with big finds.

So do you think the recent drop has created a good buying opportunity? Or is there more downside ahead? Let the community know what you think -- head over to CAPS and share your thoughts with the other 83,000-plus players currently part of the community. Even if you'd prefer to pass on Schlumberger, you can check out other stocks listed above or any of the 5,300 stocks that are rated on CAPS.

More CAPS Foolishness: