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.

  • Level 3 Communications (Nasdaq: LVLT)
  • Micron Technology (NYSE: MU)
  • Northern Dynasty Minerals (NYSE: NAK)
  • Santarus (Nasdaq: SNTS)
  • Visa (NYSE: V)

Some of these names might surprise you. For example, Visa, like its rival MasterCard, operates what could be described as a "meter drop" type of business, a phrased popularized by Wade Cook, a stock-trading seminar promoter ultimately convicted for tax evasion. As preposterous as Cook's strategies were, the concept remains valid in that Visa generates income from millions of small transactions rather than larger but fewer ones that might be embodied by a traditional credit card. Almost great? Even unfamiliar names can still offer some of the best opportunities. Perhaps we've just forgotten the potential they still hold.

Northern Dynasty Minerals might not roll off the tongue as easily as Visa, but the exploration company developing a copper, gold, and molybdenum mine in Alaska has sites on becoming the next Freeport-McMoRan (NYSE: FCX). However, the 165,000-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?
Telecom services provider Level 3 Communications disappointed investors with its earnings report last month, event though losses came in narrower than expected. Revenues turned out to be a bit short of analyst forecasts, but its core network services are expected the grow sequentially for the rest of the year and they account for more than three-quarters of Level 3's total revenues.

Analysts have been saying for some time that competition in the field was getting tighter. Akamai (Nasdaq: AKAM) has been feeling the heat from Level 3, which has also apparently neutralized Neutral Tandem.

Fiber optics growth will be key to Level 3's success, says CAPS member patryan4511, and with its stock down 32% year to date, it represents an uncommon value:

This is the largest and best company in the fiber optics field. The need is growing fast and LVLT is ready to grow with it. Buy now and go for the ride.

On the shoulders of giants
Intel may have soured the market with its dim forecast for technology, but its pursuit of a growth by acquisition strategy suggests it's looking to be ready to hit the ground running when things turn. Micron Technology aims to be right there with it and will probably seek to gain long before a turnaround becomes a fait accompli.

It's rushing off to find a pot of gold now, striking while the iron is hot. With Taiwan Semiconductor building out capacity, it's not assured the turndown will happen. Micron has posted some very strong earnings showing a robust ability to meet demand. That's why pormoonman says the trend is Micron's friend these days:

The economy will require expanded technology in the near future. Companies have held off technology expenditure but they can avoid such expenditure only so long to remain viable.

A big opportunity
The stock of drug developer Santarus still hasn't recovered from the patent ruling loss related to its heartburn medicine, Zegereid, that it suffered in April, but investors shouldn't necessarily think it's given up the ghost as generics move into market. While it has stopped promoting the drug, it's also launched an authorized generic of Zegereid, a tactic often used to blunt the impact of regular generics. And it is still receiving royalties for the drug from Merck and GlaxoSmithKline. Zegereid sales will undoubtedly shrink in future quarters, but Santarus is still working to ease the acid reflux investors felt after the original patent decision.

That could be why 97% of CAPS members rating Santarus believe it will continue to post market-beating results. As humbledutch has pointed out, it still has its financial footing: "Good earnings, strong balance and generating cashflow."

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.

Intel is a Motley Fool Inside Value recommendation. Akamai Technologies isMotley Fool Rule Breakers pick. GlaxoSmithKline is a Motley Fool Global Gains recommendation. The Fool owns shares of and has written puts on Intel. Motley Fool Options has recommended buying calls on Intel. The Fool owns shares of GlaxoSmithKline and Neutral Tandem. Try any of our Foolish newsletter services today, free for 30 days.

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.