"The bigger they are, the harder they fall." It's the worst nightmare of every investor in today's market -- buying a rocket stock just before it takes a nosedive.

I readily admit that stocks sometimes rise for a reason. But sometimes, the rise becomes the reason. No matter how often we caution them not to, investors do have a habit of buying "hot" stocks, and trusting momentum to keep them moving upwards.

Unfortunately, if the price goes up too much, even a great company can turn into a lousy investment. Below, I list a few stocks that may have done just that. According to the smart folks at finviz.com, these stocks have more than doubled since the beginning of this year, and they just might be ripe to fall back to earth.

Company

Recent Price

CAPS Rating (Out of 5):

Freeport-McMoRan  (NYSE:FCX)

$60.30

****

Baidu.com (NASDAQ:BIDU)

$348.14

***

Barclays (NYSE:BCS)

$20.54

***

Goodyear Tire  (NYSE:GT)

$17.02

**

Sprint Nextel  (NYSE:S)

$4.00

**

Companies are selected by screening for 100% and higher price appreciation year-to-date on finviz.com. Current pricing provided by Yahoo! Finance. CAPS ratings from Motley Fool CAPS.

Each of these stocks has already enjoyed remarkable gains since the year began. As a result, the stock prices are now looking awfully high -- and the natives are getting restless. Over on Motley Fool CAPS, the 135,000 (and counting) investors who make up our community of lay stock analysts don't see much hope for further gains in these companies ... with one exception.

The bull case for Freeport-McMoRan
CAPS member martynanasi, ranked in the community's top 1% of investors, argues that: "Bail out money and current deficit situation in US" add up to "inflation going higher":

Not a matter of if but when. Weak US dollar and rising treasury yield also will help toward this. These are all factors in favor of gold prices moving higher. ... which therefore makes gold a hedge toward these factors including a store of wealth.

That's all very well for the gold factor, but what about the copper? theinfamoushw likes Freeport's business in both minerals, calling the company a "commodity hedge."

And CAPS All-Star phrush agrees:

I believe the 3-5 year outlook is crystal clear. As the CEO of FCX stated, there have been NO new major sources of copper discovered anywhere in the world for years and years. With the continued development of China and India, even a permanent slowdown in the economies of the developed countries will leave us with a supply-demand imbalance, since the improved techniques which have allowed existing mines to improve the efficiency of extraction are now showing decreasing effectiveness in further gains. Thus, I not only expect copper prices to regain the level of mid 2008, but to go beyond that.

This all sounds very convincing, Fools -- but personally, I'm staying out of this debate. I don't understand cyclical stocks. Never have. Never will. Oh, I was right about the rebound in oil prices; I called the low almost precisely. But I assure you, that was nothing more than dumb luck.

Need proof? I was right about Mosaic (NYSE:MOS) outperforming the market when I picked it on CAPS back in October. But I was just as wrong when I said PotashCorp (NYSE:POT) would underperform at the same time.

When I look at Freeport, I see a company producing minimal free cash flow and trading for an obscenely high P/E relative to its projected growth rate. Therefore, I wouldn't touch it with a 10-foot shovel. But if I'm right in that assessment, it'll be nothing more than dumb luck again.

Time to chime in
Yet I know there are Fools out there who do understand cyclicals. Are you one of these savvy souls? If so, lend us a hand in figuring out what to do about Freeport. Should we buy it? Sell it? You tell me.

Motley Fool CAPS : It's fun, it's free, and it just might make you famous.

Fool contributor Rich Smith does not own shares of any company named above.You can find him on CAPS, publicly pontificating under the handle TMFDitty, where he's currently ranked No. 841 out of more than 135,000 members. The Fool has a disclosure policy.

Baidu is a Motley Fool Rule Breakers recommendation. Sprint Nextel is a Motley Fool Inside Value pick.