Some companies are obviously great investments -- in hindsight. Yet for every stock out there screaming "buy me," others simply give us a nudge and a nod. How can we tell tomorrow's obviously great investments from the thousands of pretenders?

The stars' walk of fame
On Motley Fool CAPS, these opportunities can be found among our four-star stocks. In CAPS' proprietary ratings system, they rank higher than most of the other 5,400 starred companies, but they're just shy of superstardom. While all the attention might be focused on their five-star peers, we can sift through CAPS to find four-star firms approaching greatness. Here are a handful of four-star companies approaching greatness.

  • Aeropostale (NYSE: ARO)
  • Conexant Systems (Nasdaq: CNXT)
  • Health Management Associates (NYSE: HMA)
  • Jamba (Nasdaq: JMBA)
  • L-1 Identity Solutions

Some of these names might surprise you. For example, L-1 Identity Solutions showed French aerospace leader Safran enough potential that Safran decided it wanted to buy most of the company. Almost great? Even familiar names can still offer some of the best opportunities. Perhaps we've just forgotten the potential they still hold.

And smoothie maker Jamba is reinventing itself by expanding beyond just fruit drinks. It's blending new opportunities by offering warm drinks and food to take on Starbucks (Nasdaq: SBUX) and fruit-based energy drinks that will squarely challenge Hansen Natural. As the 170,000-plus CAPS members have chosen these companies as less obvious sources for tomorrow's great buys, let's see why they might merit your attention.

In the sight of greatness?
Given that it just stumbled, with same-store sales falling 1% for November following a 2% drop in October, it might be surprising to find retailer Aeropostale on this list. Even laggard Abercrombie & Fitch (NYSE: ANF) was able to report another month of strong comps.

Yet along with Buckle, Aeropostale has been one of the outstanding retail success stories throughout this recession. The market's overreaction to the sales news created a buying opportunity that even private equity investors noticed. The retailer has hired Barclays to advise it on preventing a hostile takeover attempt.

Assuming that management succeeds in fending off any potential bidders, CAPS member echeverria says the retailer remains best in class:

ROIC best in it's industry; great inventory control, clean balance sheet. Recent sell off is an over reaction! [Aeropostale] will outperform it's peers over the next five years.

More than 91% of the CAPS members rating the retailer expect it to outperform the broad market averages. Tell us on the Aeropostale CAPS page whether you believe that it can gain altitude again.

Dirt cheap?
Fabless semiconductor maker Conexant Systems has been diligently paring down its debt-laden balance sheet using equity offerings made earlier this year. Coupled with its sales of various product lines in order to concentrate on its core business, Conexant should be able to create value for shareholders again.

It hasn't been an easy path; the semi shop anticipates a significant sequential revenue decline in its legacy businesses for this quarter. Still, CAPS member TechSci has high hopes for Conexant's new graphics chip.

Not sure whether Conexant is right for your portfolio yet? Add the stock to your watchlist to get all our Foolish news and analysis on the company aggregated for you.

A big opportunity
Mergers and acquisitions is one of the themes running throughout a number of the companies listed today. It's possible that Community Health Systems' lowball bid for hospital operator Tenet Healthcare (NYSE: THC) in November will actually be an opening for Health Management Associates to buy Tenet. Analysts suspect that HMA is the only real alternative (aside from private equity) to make a realistic bid for Tenet. But although Wall Street has cast a pall over Community's offer, Community still might come back with a higher bid that Tenet shareholders would jump at.

Thus,  investors comparing Health Management Associates to either Community or Tenet may find HMA the better choice. Rate or read about the hospital operator on the Health Management Associates CAPS page, and add the stock to the Fool's free portfolio tracker.

A great opportunity for you
Investor sentiment suggests these four-star investments still seem to be on their way to five-star greatness, but it pays to start your own research on these stocks on Motley Fool CAPS. Read a company's financial reports, scrutinize key data and charts, and examine the comments your fellow investors have made, all from a stock's CAPS page.

Sign up today for the completely free service and let us hear what you have to say about the great and almost-great companies that interest you.

Hansen Natural is a Motley Fool Rule Breakers recommendation. Starbucks is a Motley Fool Stock Advisor pick. The Fool owns shares of Aeropostale. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.

Fool contributor Rich Duprey owns shares of Aeropostale but does not have a financial position in any of the other stocks mentioned in this article. You can see his portfolio. The Motley Fool has a disclosure policy.