Big things do come in small packages. Diedrich Coffee (NASDAQ:DDRX) is a fine example of that axiom -- in more ways than one.

First, the coffee roaster decided to refocus on selling Keurig K-Cup coffee. Diedrich has become a leading provider of coffee for those Keurig quick-and-easy cups o' Joe under license from Green Mountain Coffee Roasters (NASDAQ:GMCR), and Diedrich has staged a massive turnaround based on those tiny servings of black gold. That's one small package for you.

As a direct result of that fundamental little revolution, Diedrich's stock has bounced back like no stock I've ever seen. Coming back off a 52-week low of $0.21 per share this spring, Diedrich's market cap was a paltry $1.2 million at one point. If that's not a small package, I don't know what is. And now the turnaround is complete and the stock sports a price near $25.80 per share.

If you do the math, you'll see a heart-stopping 12,200% return on your investment if you were brave and lucky enough to buy during Diedrich's darkest hour. And it is virtually locked in, because today's price includes the 28% premium that Peet's Coffee & Tea (NASDAQ:PEET) is paying to acquire the company. Diedrich is trading very close to Peet's $26 cash-and-stock offer, leaving little room for arbitrage.

The buyout must have come as a shock to Diedrich's management. Less than two weeks ago, Diedrich announced that CEO Russ Phillips was stepping down. Recruitment specialist Korn/Ferry International (NYSE:KFY) had started looking for a replacement. And now it's a moot point.

Peet's distribution system plus Diedrich's hot products and top-notch coffee roasting processes should add up to something greater than the simple sum of the parts. Sure, even with Diedrich under its wing, Peet's is still a far cry from the multibillion-dollar sales of Starbucks (NASDAQ:SBUX), but the single-serving business is booming. Diedrich reported sales of $62 million in fiscal 2009 but expects to deliver more than $90 million in 2010 revenue.

Don't kick yourself too hard if you missed out on Diedrich's extravagant gain. Longtime shareholders are doing fine, as the stock has delivered better than 440% gains over the last five years and 640% over the last three. But as we've seen, in between, Diedrich teetered on the brink of extinction.

This is exactly the kind of roaring-back-to-life move you're hoping for if you are buying Sirius XM Satellite Radio (NASDAQ:SIRI) or Crocs (NASDAQ:CROX) these days. Feel free, pal. But remember the sordid stories of Circuit City and Nortel Networks before you hit that "buy" button: Some turnarounds never turn.

Diedrich scared the heebee-jeebies out of fellow Fool Dan Caplinger after that roller-coaster ride. Do you see any surefire turnarounds among the other monster stocks of this Fooloween?

Fool contributor Anders Bylund holds no position in any of the companies discussed here, though he briefly owned a few shares of Diedrich back in 2005. He is missing out on some huge gains because he didn't have the nerve to sit out the bad times. Green Mountain Coffee Roasters is a Motley Fool Rule Breakers selection. Starbucks is a Stock Advisor pick, and the Fool owns shares of it. Try any of our Foolish newsletters today, free for 30 days. You can check out Anders' holdings and a concise bio if you like, and The Motley Fool is investors writing for investors.