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 firms approaching greatness.

  • Amerigroup (NYSE: AGP)
  • ArenaPharmaceuticals (Nasdaq: ARNA)
  • Brocade Communications (Nasdaq: BRCD)
  • Coeur D'Alene Mines (NYSE: CDE)
  • Kodiak Oil & Gas (NYSE: KOG)

Some of these names might surprise you. For example, Amerigroup was able to post higher fourth-quarter profits based on the strength on premium increases it was able to push through. Almost great? Even familiar names can still offer some of the best opportunities. Perhaps we've just forgotten the potential they still hold.

It was the potential for new silver and gold operations that attracted many investors to Coeur d'Alene Mines, and the news that silver production jumped 47% while gold was up 56% last year has to give them hope for better times ahead. More than 1,300 CAPS members have rated the miner and 95% have said it will outperform the broad market averages.

However, the 160,000-plus CAPS members 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?
It's not exactly like digging up nuggets of gold, but Kodiak Oil & Gas was able to narrow its losses from a year ago as revenues quadrupled. The results were still below what analysts had been anticipating, however, but 94% of CAPS members maintain a positive outlook for the future of the independent energy exploration and development company.

That's a similar percentage of CAPS members who are looking for Arena Pharmaceuticals to succeed. It announced last week that within three months of the FDA approving its obesity drug locaserin -- a decision that is expected by the end of October -- it will launch the drug, either on its own or with a partner. Arena is competing against VIVUS (Nasdaq: VVUS) and Orexigen Therapeutics (Nasdaq: OREX) to get to market with a weight loss drug, which would be the first prescription drug approved in 10 years.

VIVUS's Qnexa has produced some outstanding results in late-stage trials while Orexigen says it plans to file for regulatory approval of its Contrave drug before the end of April and has signed up a Canadian drug maker to manufacturer it.

CAPS member SuperGrowth237 has two reasons for thinking Arena will be the winning stock, one of which is this:

Even if the FDA does NOT approve the drug (btw it is by far the safest obesity drug up for approval in near future) the stock price will rise considerably in anticipation of the October decision. This could easily double as more and more investors hear of ARNA and realize that their drug has a good chance of being approved. Buy now @ 3.00 and watch it hit at least 4 in anticipation of decision.

Check out his other reason on the Arena Pharmaceuticals CAPS page where you can share with us your own weighty thoughts on the matter.

On the shoulders of giants
Brocade Communications will never make you look svelte, but CAPS member amanalvi says its storage business will grow, recent results notwithstanding, ultimately making your portfolio look more trim:

storage business is growing and with positive cash flow and developing market for its foundry branch company has a bright future and its a possible buyout target for companies want to expand in computer storage business. Not cheap but nice entry point for long term investment as fundamentals are improving.

More than 630 CAPS members mark the data storage specialist to outperform the market and we'll store your view of its chances for success on the Brocade Communications CAPS page, or in the comments section below.

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.

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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.