"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.

Now I readily admit that sometimes, stocks 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 'em moving upwards.

Problem is, 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. Stocks that, according to the smart folks at finviz.com, have more than doubled since the beginning of this year, and just might be ripe to fall back to earth.

Stock

Recent Price

CAPS Rating
(out of 5 stars)

Thompson Creek Metals  (NYSE:TC)

$9.92

*****

Research In Motion  (NASDAQ:RIMM)

$82.70

**

Sirius XM Radio  (NASDAQ:SIRI)

$0.34

**

Sun Microsystems  (NASDAQ:JAVA)

$9.17

**

Micron Technology  (NYSE:MU)

$5.30

**

Companies are selected by screening for 100% and higher price appreciation year-to-date on finviz.com. Five stars = highest possible CAPS rating; one star = lowest. Current pricing provided by Yahoo! Finance. CAPS ratings from Motley Fool CAPS.

Tech stocks have enjoyed some remarkable gains over the past five months, no doubt. But if you ask the 135,000 (and counting) investors who make up Motley Fool CAPS, it's high time that tech got its comeuppance. Where do they suggest you put your money instead? Which rally has the stronger "legs"?

Commodities. And in particular ...

Thompson Creek Metals
Never heard of Thompson Creek? Then let's have CAPS All-Star TSIF make the introductions:

Thompson Creek is a Canadian company with most of it's assets in the US. It's core output, molybdenum products, has had a serious price squeeze in this recession. Despite this Thompson Creek has remained profitable and is expanding. ... Margins are strong, cash flow postitive, cash on hand above average for a miner while debt is almost nil.

In case you (like me) are now thinking that all this is well and good but ... "what the heck is molybdenum," then we'll turn next to fellow All-Star forexnutca for a quick primer in the metal:

Moly [is] a metal used in all kinds of applications. In its nano-particle form it can be used for nuclear reactor fuel, fuel cells, optic fibers, and plasma TV's. It is also being developed in conjunction with Li-ION batteries. Both cycling stability and rate capability issues with current generation LI-ION batteries are addressed by employing these porous molybdenum oxide films that consist of nanoscale active particles. This will be key in hybrid vehicles and consumer electronics of the future- (more recharges, and less power loss).

Plasmas and hybrids and nuke plants (oh my!). Assuming anyone has disposable income left to spend on these high-tech wonders when the recession ends, All-Star SmallCapsInvstr predicts: "Other than moly prices being low currently, this pick looks great. An incredible value right now for a company that looks like they have a bright future."

I have to tell you, Fools, I don't usually invest in miners myself -- I've never liked cyclical industries enough to be tempted. But Thompson Creek? This company just might be my first. Why?

Well, according to the newspapers, things are in a bit of a funk right now. Thompson Creek is certainly feeling the pain of molybdenum prices that are about one-third those of last year: first-quarter profit dropped 76% from the year-ago period. Yet as bad as things are in the world at large, here we find Thompson Creek making enough to earn itself a P/E just above 8. Plus, it generated $278 million in trailing free cash flow (a price-to-free cash flow ratio of 4.4), and carries more than $240 million in net cash on its balance sheet.

Not debt. Cash. In a world where miners such as Freeport-McMoran (NYSE:FCX) and Rio Tinto (NYSE:RTP) habitually flip things around and carry balance sheets heaped with debt, I find Thompson Creek's cash-heavy warchest incredibly attractive. And the fact that this company is so darn skilled and digging up more green, year after year? For me, that clinches the argument. I'm all but persuaded to take a dip in Thompson Creek myself.

Foolish takeaway
But perhaps you are not? You see, the aim of this column isn't just to tell you what I think about Thompson Creek Metals -- or even what other CAPS players are saying. We really want to hear your thoughts. Click on over to Motley Fool CAPS and tell us what you think.

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. 918 out of more than 135,000 members. The Fool has a disclosure policy.