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, you can find these opportunities among our four-star stocks. In CAPS' proprietary ratings system, they rank higher than most of the other 5,300 starred companies, but they're just shy of superstardom. While their five-star peers get all the attention, we can sift through CAPS to find four-star companies approaching greatness. Here are a handful.

  • Allos Therapeutics (NASDAQ:ALTH)
  • ATP Oil & Gas (NASDAQ:ATPG)
  • Cisco (NASDAQ:CSCO)
  • Oracle (NASDAQ:ORCL)
  • Take-Two Interactive (NASDAQ:TTWO)

Some of these names might surprise you. Enterprise-software specialist Oracle, for example, has been a household name since it emerged in the tech boom. 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-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?
Preventing and curing illness and disease isn't the only end game for drugmakers. Improving quality of life or ameliorating some of the more serious effects of an illness can sometimes be just as important. For example, Japanese pharmaceutical Eisai and Pfizer (NYSE:PFE) manufacture and market the top-selling Alzheimer's treatment Aricept, even though it only temporarily improves patients' cognitive abilities, since there is yet no cure. Even so, Aricept makes for a lucrative endeavor, as Eisai generated more than $3 billion in revenues from the drug last year.

The ability to profit from relieving or reducing symptoms made it important for Allos Therapeutics to get FDA approval for its injectable drug Folotyn, a treatment for rare, aggressive lymphatic cancers. It's not that Folotyn cures the tumors -- it doesn't; it merely reduces their size -- but because there are no other treatments available for peripheral T-cell lymphoma, Allos has a unique opportunity to generate sizable revenue. Now that Allos has received an expedited approval, it plans to begin marketing the drug next month.

Peripheral T-cell lymphoma is a form of non-Hodgkins lymphoma. The American Cancer Society estimates that 66,000 new cases of non-Hodgkins lymphoma are diagnosed every year, 10% to 15% of which are of the PTCL variety. Allos is also looking at Folotyn as a treatment for bladder and lung cancer, as well as for treating solid tumors, head and neck cancer, and breast cancer.

More importantly, as CAPS member gorfo57 notes, the FDA's approval of Folotyn allows Allos Therapeutics to begin generating revenue from product sales for the first time ever. CEO Paul Berns calls this a "transformative event" for a company that's been developing cancer treatments for 14 years.

With this approval, Allos is going to have to make a milestone payment of $5.3 million to the developers of the drug, but that shouldn't be a problem since it has more than $100 million in cash and short-term investments sitting in the bank.

A little give and take
E&P play ATP Oil & Gas got investors pumped with a report saying it discovered approximately 250 net feet of logged hydrocarbon pay in the Gulf of Mexico at its Telemark Hub, an amount that effectively doubles its predrill estimate. It's also more than three times the amount of net feet of logged hydrocarbons found at its Vastar discovery well and will increase ATP's production, along with its proved and probable reserves.

The stock more than doubled this month, but it quickly gave a bunch of those gains back when it followed up the discovery news with an announcement that it was launching a 5.3 million-share offering that would dilute current shareholders by at least 12%. That follows the lead of Delta Petroleum (NASDAQ:DPTR), which also resorted to issuing more shares to raise capital.

Still, highly rated CAPS member xiaolifeidao finds ATP to have a predictable business model that can be easily valued.

This one is a good example that the stock price follows P/book-value or P/E and it is PREDICTABLE. At the prices of $8 two months ago, the market value was almost the same as book value, which was too low. In less than 2 months, the stock prices jumps 100% and makes me very happy since I played it for real.

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

Take-Two Interactive Software is a Motley Fool Rule Breakers recommendation. Pfizer is a Motley Fool Inside Value pick. Try any of our Foolish newsletter services free for 30 days. The Motley Fool owns shares of Oracle.

Fool contributor Rich Duprey has no financial position in any of the stocks mentioned in this article. You can see his holdings. The Motley Fool has a gold-plated disclosure policy.