The market is having a horrendous year; today, it’s wrapping up one of the worst months in stock market history. The stock of exchange operator NYSE Euronext (NYSE:NYX) haven’t been spared -- it’s lost almost 70% of its value with respect to its 52-week high. That carnage has sown the seeds of opportunity for patient investors.

The underlying business remains strong; as evidence of this, I’d like to enter into the record NYSE Euronext’s third-quarter results, which were announced this morning. The market-jury was swayed: As I write this, the stock is up more than 8%, with the broader market up around 2%.

Including non-recurring items, quarterly revenue increased 16% over the prior-year quarter (market volatility has lifted trading volumes nicely), while diluted earnings per share fell 4% to $0.72.

In this unprecedented environment, some investors must wish John Thain were still at the helm. Thain, who came from Goldman Sachs (NYSE:GS), skillfully transformed the NYSE before going on to save Merrill Lynch (NYSE:MER) through a sale to Bank of America (NYSE:BOA). Not to worry, though -- the current CEO, Duncan Niederauer, was Thain’s protegee and is a former Goldman executive, too.

Place your CDSs on the counter
Volatility isn’t the only opportunity for exchanges right now. Mounting fears and scrutiny of the $55 trillion over-the-counter credit default swap (CDS) market -- CDSs were instrumental in sinking insurer AIG (NYSE:AIG) -- create huge opportunity for exchange operators that can offer solutions in terms of centralized clearing of trades and counterparty risk management. As the owner of European derivatives exchange LIFFE, NYSE Euronext is part of that conversation (along with firms such as CME Group (NASDAQ:CME)).

From overvalued to value play
As I see it, NYSE Euronext’s stock has spent much of the last two years being substantially overvalued. Now is not one of those times: With the most pessimistic analyst calling for the company to earn $2.99 next year, the stock looks positively attractive at approximately 10 times that estimate. On that narrow basis, it even outshines its sprightly rival, Nasdaq OMX (NASDAQ:NDAQ).

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