Buying great companies at cheap prices is a proven strategy for beating the market.

Alas, such a strategy is easier to articulate than to execute. For example, Amazon.com (NASDAQ:AMZN) and Starbucks (NASDAQ:SBUX) are clearly great companies. But are they good values at their current prices? And Freddie Mac (NYSE:FRE), which has declined by roughly 60% over the past year, may well be a decent value at the current price, but is it a great company? The same question might be asked about its sibling, Fannie Mae (NYSE:FNM), which has declined by more than 40% over the past 52 weeks.

Recognizing the inherent challenges in identifying great but cheap companies, we asked for help. During the course of a weekend when many folks were out rummaging through malls across America hunting for bargains, we asked our CAPS community to uncover the very best bargain stock out there.

And the winner is ...
Our community members have cast their votes, and the results are in. Cemex (NYSE:CX) -- a company Bill Mann has dubbed the Wal-Mart of cement -- is the winner of our "Best Black Friday Bargain Stock" contest.

The voting was close. Indian car maker Tata Motors (NYSE:TTM) finished second, while Portfolio Recovery Associates (NASDAQ:PRAA) placed third. It's interesting that two of the top three are international companies, which may reflect the market's overall enthusiasm for foreign stocks recently.

Just one word ...
Cement. Yep, our contest winner is the third-largest cement company in the world. This company, which was recommended by Bill Mann in the June 2007 issue of Motley Fool Global Gains, dominates the Mexican cement market and has operations in more than 50 countries. As fellow Fool Anand Chokkavelu recently noted, Cemex's share price is down more than 35% since the summer, most likely because it was incorrectly tied to the U.S. housing market. Anand argues persuasively that Cemex's exposure to the U.S. market is limited -- indeed, the company is broadly diversified across different markets.

Bill Mann is equally enthusiastic about Cemex, having declared back in June that he expects this "$25 billion market cap company will be worth $50 billion or more within three years."

What do you think, Benjamin?
Both Anand and Bill have laid out a persuasive case for Cemex. But the risks associated with this company are considerable. The subprime crisis and resulting credit crunch have pretty much indiscriminately affected any company with even the slightest hint of exposure to the U.S. housing market. Add to that the risks associated with a company that does business in many developing markets, and you can begin to see why there is a degree of uncertainty surrounding this stock.

Let us know what you think by posting your own thoughts about Cemex on CAPS. Just click here to join up. It's entirely free to do so.

Cemex is a Motley Fool Global Gains recommendation. Starting today, a team of Global Gains analysts will be visiting Argentina, Chile, and Brazil to find the best investment ideas those countries have to offer. To get our real-time reports from the field (for free), simply provide your email address in the field below.

John Reeves does not own shares in any of the companies mentioned above, though he does have an unopened bag of cement in his shed at home. Portfolio Recovery Associates is a Motley Fool Hidden Gems pick. Cemex, Amazon.com, and Starbucks are Motley Fool Stock Advisor recommendations. Fannie Mae and Wal-Mart are Inside Value selections. The Fool has a disclosure policy.