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 5,300 rated 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 companies approaching greatness. Here are a handful.

  • Brigham Exploration (NASDAQ:BEXP)
  • Coca-Cola (NYSE:KO)
  • Elan (NYSE:ELN)
  • Hansen Natural (NASDAQ:HANS)
  • Mahindra Satyam (NYSE:SAY)

Some of these names might surprise you. Soda giant Coca-Cola, for example, has tickled our noses with its carbonated beverages for more than 100 years. Almost great? Even familiar names can offer some of the best opportunities. Perhaps we've just forgotten the potential they still hold. However, the 140,000-member CAPS community chose these companies as less obvious sources for tomorrow's great buys, so let's see why they might merit your attention.

In the sight of greatness?
Pharmaceuticals giant Johnson & Johnson's (NYSE:JNJ) taking an 18% stake in Elan serves as something of an endorsement for the biotech to rediscover its growth plans. As CAPS member latimerburned noted, Elan will now be able to focus exclusively on its drugs:

They have taken away a lot of the financial risk with the [J&J] deal so now its all about Tysabri and Alzheimers. I think that the benefits of Ty outweigh the risks as they are learning how to manage the drug so this one should do very well.

Well, apparently they're going to need to do just that because the SEC wants more information about certain data concerning it and Biogen Idec's MS drug, Tysabri, and its Alzheimer's investigative drug, bapineuzumab. The agency wants to look further into Elan's July statement that there were two additional cases of a deadly brain disease in patients using Tysabri, as well as some phase 2 trial data from bapineuzumab.

Despite the risks, there are many reasons to be invested in Elan and its drug Tysabri, and though competition will be upon them soon enough, there are more than a few smart Fools who see the Motley Fool Rule Breakers recommendation as being the strongest biotech to lead them.

Time to bulk up
Another Rule Breakers selection that's making its mark is beverage maker Hansen Natural. After a string of quarterly losses, the Monster Energy drink mixer recorded a profit that has seen shares surge more than 28% over the past three months. Analysts, though, are hedging their bets, believing it's unlikely to ramp up domestic sales sharply enough to justify the valuation Wall Street has placed on the stock.

That may be shortsighted. Using the distribution networks of both Coca-Cola Enterprises and Anheuser-Busch InBev, Hansen's products have been getting the shelf space they need to grow sales. While analysts may have wanted stronger volume and revenue growth from domestic markets, the increases Hansen achieved came about while PepsiCo (NYSE:PEP) and Coke watched their energy-drink sales fall.

Growing sales, a strong balance sheet, and a good management team are enough for CAPS member djveed to see this becoming a monster stock again:

Recently turned a profit after a tough five quarters or so. Well managed with little to zero debt. Great cash management.

A great opportunity for you
Investor sentiment suggests these four-star investments are 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.

Elan and Hansen Natural are Motley Fool Rule Breakers recommendations. Coca-Cola is an Inside Value pick. Johnson & Johnson, Coca-Cola, and PepsiCo are Income Investor selections. A 30-day subscription is available to each of those newsletters for free.

Fool contributor Rich Duprey does not have a financial position in any of the stocks mentioned in this article. You can see his holdings here. The Motley Fool has a gold-plated disclosure policy.