While they may be a little tricky to classify, there is no doubt that the land of mid-size marvels can present its fair share of opportunities. Here is a look at three companies that may just fall into that category.

Beer me!
OK, maybe just stock me ... with a few shares of Molson Coors Brewing Company (NYSE: TAP). Unless you live under a rock, then chances are you have heard of at least one of the brands this company sells. Molson purveys everything from Coors Light and Miller Lite to the more "cosmopolitan" Molson and crafty Blue Moon, and their beers are available in more than 30 countries around the globe.

The company is broken down into three major business units serving markets in the United States (MillerCoors), Canada (Molson Coors), and the UK (Molson Coors-UK), and they hold significant market share in each with almost 30% in the US, 40% in Canada, and 19% in the UK. While top-line revenues have been down lately, the company sees better days ahead as they continue to execute on their strategies for innovation and cost savings.

Molson has stated that unemployment coupled with low consumer confidence continue to present challenges. However, barring prohibition (and we all know how that worked out last time), beer is going to be consumed. And with its catalog of popular potations to go along with its potential to generate some serious cash flow, I can see Molson being worth a lot more than what it is selling for today.

The company generated about $775 million in free cash flow over the past twelve months and is selling at about 11 times this today. Economic recovery is going to have a huge ripple effect with a company like this, and at these prices, Molson is looking pretty tasty right about now.

Let's talk insurance
There is always a lot of chatter at Motley Fool HQ about Berkshire Hathaway (NYSE: BRK-B) and its legendary leader Mr. Buffett. Alleghany Corporation (NYSE: Y) is another insurance operation that is run with many of the same philosophies that have brought Buffett so much fame and fortune. On the face of it, Alleghany's business is based on property and casualty, and surety insurance. However, they are more than just that.

Insurers, as you probably know by now, generate a substantial portion of their earnings from their investment portfolios, and they feed these portfolios with the cash they pull in from premiums paid to the company. Now, insurance itself is a very low-barrier business; therefore, the good ones need to separate themselves in order to stand above the crowd. In Alleghany's case, they take a very conservative approach in their business philosophy. This statement from the company's website says a lot:

We shun investment fads and fashions in favor of acquiring relatively few interests in basic financial and industrial enterprises that offer the potential to deliver long-term value to the investor.

Sound familiar? It should if you follow Berkshire at all. Alleghany's return on equity has averaged a little better than 10% annually over the past ten years, which is not too shabby for a company with a conservative bent. Top that off with a share price that has increased at a compound annual growth rate of a little better than 7% over the past ten years, and we may have just found a nice place to park some of our hard-earned money.

Insurance in general has been witnessing a soft market lately, and shares of Alleghany are trading today at tangible book value that is historically low. This could be an excellent time to insure your portfolio with some stability a la Alleghany.

Field of dreams
Looking for a way to play the fertilizer field? Nitrogen and phosphate fertilizer producer CF Industries (NYSE: CF) looks like a solid prospect. While nitrogen is important for plant growth and high crop yields, phosphate helps plants generate necessary sugars for development as well as strong roots. As such, CF's products are quite cyclical as they are based on demand from farmers who grow everything from corn to cotton and wheat.

The company just recently completed its acquisition of fellow competitor Terra Industries, which helped increase its production and distribution capability substantially, allowing them to compete more effectively against larger competitors like Mosaic (NYSE: MOS).

Recent business combination costs contributed to the company reporting a loss for the first quarter of 2010. However they see the outlook as favorable going forward based on higher demand due to more planted acreage and ideal weather conditions. With synergies from the acquisition as well as an increased customer base, the company will be able to better meet future fertilizer demand as it arises in the field.

Add to this capacity a bulletproof balance sheet flush with more than $1 billion in net cash, and I like CF's chances. CF is currently trading at an EV/EBITDA of 6, but this is really a bet on the cyclicality of nitrogen and phosphates. As the economy continues to heal and demand comes back around, look for CF's stock price to follow suit.

As always, these are suggestions for further research and not formal recommendations. Mr. Market has been known to overlook the mid-cap marvels from time to time, as he is often more focused on the headliners. Keeping an eye out for the ones that are flying under the radar can lead to some heady returns.

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