An unlikely group of stocks have led the market and gained +123%, +162%, +535% — even +7,233% this year. They still have room to climb.

These companies defied Wall Street’s expectations as consumers clamored for a product they just couldn’t live without. It’s not oil. It’s not drugs either.

A hint: 54% of American adults drink it every morning. It’s coffee, the beverage that delivers three-quarters of the caffeine consumed in the United States.

Americans are becoming more particular about what kind of coffee they drink, demanding more premium blends than ever before. Before Starbucks (Nasdaq: SBUX), Americans asked a waitress for “a cup of coffee.” Today, baristas take requests for a “venti, half-caff, sugar-free vanilla skim latte.”

In any case, coffee is a serious business dominated by several key players: 

Company (Ticker)	P/E	Forward P/E	YTD Return
Green Mountain (Nasdaq: GMCR)	64.0	59.4	+162%
Diedrich (Nasdaq: DDRX)	110.0	26.0	+7,233%
Starbucks (Nasdaq: SBUX)	26.4	22.0	+123%
McDonald’s (NYSE: MCD)	16.2	15.6	+0.8%
Caribou (Nasdaq: CBOU)	39.3	26.2	+535%
Peet’s Coffee and Tea (Nasdaq: PEET)	40.5	37.4	+65%

It didn’t take long after Starbucks appeared before McDonald’s (NYSE: MCD) and Dunkin’ Donuts took notice. They began offering their own premium blends.

Now, however, trends hint investors may find opportunity elsewhere.

For instance: The National Coffee Association says consumers drank the same amount of coffee during the downturn. What did change was where they drank it.

#-ad_banner-#People are opting to make more coffee at home or work in lieu of spending money on premium offerings from their neighborhood coffee shop. Partly fueling this trend is the Keurig coffee brewer, made by Green Mountain Coffee Roasters (Nasdaq: GMCR). The Keurig sells for about $100 and brews a single cup of gourmet coffee in less than a minute. Sales of the Keurig jumped +187% last quarter, which has propelled Green Mountain’s shares more than +160% this year.

Single-serving coffee isn’t a fad, it’s a mainstream movement. Wal-Mart (NYSE: WMT) began selling the Keurig this year. And Jarden (NYSE: JAH), owner of the venerable Mr. Coffee brand, entered into an agreement with Green Mountain to develop a cheaper single-serve brewer.

Green Mountain looks like it has a bright future, but its shares are not cheap.

Instead, the opportunity seems to be a company that makes “K-cup” packets, the single-serving coffee packets the Keurig uses. Only four coffee makers are licensed to make K-cup coffee, but the new leader will be Peet’s Coffee and Tea (Nasdaq: PEET).

Peet’s is a specialty coffee roaster that sells its products through grocery stores, home delivery, offices and foodservice channels. The company acquired another up-and-comer from the table above, Diedrich Coffee (Nasdaq: DDRX), last week.

Diedrich’s sole business is in the K-cup market. Shares of the company traded for about $0.21 in March and were up +7,000% before Peet acquired it for $26 a share on November 3. The market cheered the deal when it was announced and sent Peet’s shares up +11%, which is uncommon for an acquiring company.

The deal should prove to be a winner for Peet’s in the long run. Diedrich has strung together three quarters of profitability and its K-cup brands combined with Peet’s distribution channels should prove to be a strong tailwind.

This isn’t value investing, thought. Green Mountain is pricey and at 37 times earnings Peet’s shares aren’t particularly cheap: Investors are clearly being asked to pay a heady premium for growth.

But Peet’s should deliver in that department: Executives say the new company’s combined earnings could double by 2011. Investors looking for a proven growth stock with room to climb should consider Peet’s.