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.

  • Applied Materials (Nasdaq: AMAT)
  • Bucyrus International (Nasdaq: BUCY)
  • Caterpillar (NYSE: CAT)
  • Frontline (NYSE: FRO)
  • Yamana Gold (NYSE: AUY)

Some of these names might surprise you. For example, Caterpillar is an essential bellwether component of global economic recovery. Almost great? Even familiar names can still offer some of the best opportunities. Perhaps we've just forgotten the potential they still hold.

Frontline will also be an indicator of how economic expansion is faring. As it, General Maritime (NYSE: GMR), and Teekay ship oil to the four corners of the globe, a lot will depend on how much demand is being generated. Their profitability, though, will depend in part on a recovery in shipping rates, too. 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?
Bucyrus International is no stranger to the winds of economic expansion and contraction. Manufacturing draglines, shovels, and drills for mining operations, Bucyrus investors might be willing to suspect their company is going to surprise the market if Caterpillar's trends are any indication. Machine sales in North America jumped 15% in May for the heavy equipment maker, and analysts suspect it may have been the mining segment that caused the leap.

CAPS member Jdragon80 says that having purchased the mining division from Terex, Bucyrus has positioned itself as a one-stop shop for mining companies:

The recent acquisition of the Terex mining division, specifically the trucks division will not only drastically increase revenue, but will also attract new customers who want a "single source" for their mining needs-which Bucyrus has now become. The stock is off over 30%s from it's 52 week high and represents a huge bargain. If China growth resumes it's upward trend, it will only further benefits this large mining play.

On the shoulders of giants
CAPS member kahunacfa correctly called the changing gears in the chip cycle last month, suggesting we're poised to see higher earnings in the near future for Applied Materials:

The semiconductor capital spending cycle is just starting to emerge. First come the new orders, then the backlog of equipment orders starts to build, followed by steller earnings results.

Applied Materials(AMAT) is a BUY, BUY, BUY. So is the microcapitalization company Nanometrics(NANO).

According to Semiconductor Equipment and Materials International, North American semiconductor equipment makers posted $1.48 billion in average worldwide bookings in May, up 2.8% from the month before. They noted that orders have increased for 14 consecutive months, developments that should undoubtedly benefit Applied Materials, KLA-Tencor, and wafer probe testing equipment maker FormFactor.

A big opportunity
Whether or not we hit Peter Schiff's dramatic $5,000 an ounce call for gold, it's apparent that the factors are in place for gold to continue its ascent to new heights. Rather than buying bullion or ingots, miners remain perhaps the better option for investors to take part in the new gold rush. Goldcorp (NYSE: GG) would be a leading contender for inclusion, but also Yamana Gold, which could perhaps be the real golden nugget of them all.

Superdrol remains skeptical, however, believing the gold bugs have read the stock and the precious metal wrong:

May outperform in the short-term, but unhedged (gambling) gold producers combined with lack of past profitability, strength of the dollar, pressure on commodities, the end result is these falling back to the ground.

Gold isn't an investment, it never has been. It is a trading tool, nothing more, nothing less. It's a shame people consider gold an 'investment'. Couldn't be futher from the truth.

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.

FormFactor is a Motley Fool Hidden Gems pick. Motley Fool Options has recommended a bull call spread position on FormFactor. The Fool owns shares of FormFactor and Terex. 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.