"The bigger they are, the harder they fall." This old saying sums up the worst nightmare of every homeowner, every gold buyer, and every investor in today's market. Dare ye buy at the top?

Every day, MSN Money publishes a list of the market's top stocks -- the companies whose shares have just hit their highest intraday price of any time in the past 52 weeks. Every day, investors read this list and tremble -- some with greed (big mo', baby!), and others in pure, unmitigated, acrophobic terror (whatever you do, don't look down).

Over on Motley Fool CAPS, thousands of investors just like you are watching these same companies and voting their guts on whether they'll keep rising or stumble and fall. Usually, the ratings wax optimistic as stocks hit new highs -- because everyone loves a winner. But what do you make of it when some of the smartest investors out there are panning a hot stock?

You could heed them. You could ignore them. You could take the stock tickers and construct anagrams from them. For my money, though, the best course of action is to use the "52-week highs" list as just a starting point for further research. After all, stocks can go up for many reasons, and it's up to you to decide how worthy those reasons are. But thanks to Motley Fool CAPS, now you don't have to make the decision alone.

With that said, let's meet today's list of contenders, drawn from the latest "52-week highs" list at MSN Money. What does our panel of more than 21,000 stock gurus (and counting) have to say about them?

One year ago today

Currently fetching

CAPS rating (out of five stars)

Allegheny Technologies (NYSE:ATI)

$50.65

$102.30

****

Martin Marietta (NYSE:MLM)

$88.02

$117.72

****

Cummins (NYSE:CMI)

$98.95

$139.34

***

Potash (NYSE:POT)

$93.21

$156.81

***

Vulcan Materials (NYSE:VMC)

$73.13

$103.03

**

Deere (NYSE:DE)

$73.09

$104.33

**

Companies are selected from the "New 52-Week Highs" list published on MSN Money on the Saturday following close of trading last week. CAPS ratings from Motley Fool CAPS.

Back to school
Wall Street went old-school this week in a fit of buying, driving some of the most venerable names on the NYSE to the highest heights. Whether it's involved with making metals or fertilizer, digging up rocks, or churning out horsepower, every company on this list has one thing in common: They're all hitting their 52-week highs.

Ordinarily, stocks hitting such heights are the cool kids on the block -- popular stocks sporting four and five stars from their adoring investor fans. Not today, however. Although Allegheny and Martin Marietta (no, not the plane maker -- the other one) are loved well enough, our lay analysts have their doubts about rock jock Vulcan Materials, and tractor maker Deere as well.

Why are Fools so down on these two? It's hard to tell from the few comments we've yet received. On Deere, CAPS newcomer Scruberator thinks the company is too "dependent on consumer and small business spending," and gives Deere the thumbs-down based on fears of how a slowing economy will hurt these potential buyers. And Vulcan's only negative comment comes from CAPS novice AssetMangler -- and it's a highly conflicted "negative" at best. Says AssetMangler: "Hmmm ... I'm long Florida Rock in the real world -- should I be doing this? ..."

Clearly, we need more input on these two companies before concluding that Wall Street has pushed their prices too high. And so today I'll end this column with a plea: Do you speak Vulcan? Do you drive a Deere? Then come and visit us on CAPS and lend us the benefit of your wisdom. Tell us if you think either company will outperform the S&P -- and more importantly, tell us why.

If you're proven wrong over time, there's no shame in that. (Hey, look at Jim Cramer's rating -- and he's still a pretty popular guy.) But if you're right... ah, then your call will be immortalized in hypertext, your wisdom shouted from the rooftops, and your CAPS rating will soar.

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 32 out of well over 21,000 raters. The Fool's disclosure policy is practicing its "boo-yah."