Lately, there's been speculation about whether the price of shares in TurboChefTechnologies (NASDAQ:OVEN), which makes high-speed ovens that can cook a 12-inch frozen pizza in three minutes, will soar.

Share prices could go up, especially if TurboChef lands another big contract like the one it did from Subway. Sales to other customers besides Subway are rising, and Starbucks is testing the ovens. There's talk about fielding a version targeted at households.

TurboChef could be taking a big risk by selling only high-speed ovens. Luckily, this risk is paying off for now, and TurboChef is experiencing phenomenal growth.

Second-quarter revenues were $10.8 million, compared with $2.4 million a year ago, though off from the roughly $13 million analysts had projected. The net loss was $0.21 per share, or $0.03 better than a year ago, and included a $2.8 million one-time charge.

It's difficult to put TurboChef's results in perspective because early last year it had no major contracts and traded over the counter before hop-scotching from the American Stock Exchange to the Nasdaq, with a reverse stock split along the way.

But it still seems risky because it's basically a one-product company that sells something that is nonessential, and these one-product companies often come out of nowhere to become the hottest thing around only to be sunk by some snafu. Will consumers, for example, accept their household version? Could the company expand too quickly for its own good, something that happens all the time on Wall Street?

Look at other one-product companies such as TaserInternational (NASDAQ:TASR), TiVo (NASDAQ:TIVO), and KrispyKreme Doughnuts (NYSE:KKD).

A too-rapid expansion strategy and questionable accounting practices spoiled the Krispy Kreme experience for consumers and investors alike.

Taser faces journalists, lawyers, and researchers looking to cast doubt on the product. I am aware that the 50,000-volt gun maker has a large Foolish following. Perhaps no one will ever prove that Tasers kill people, but I'd bet the journalists, lawyers, and researchers will keep trying.

TiVo has another problem: Its main client, DirecTV (NYSE:DTV), just announced plans to stop marketing its product. Scores of DVR competitors are overrunning the companies' prospects.

Compare these companies with Apple Computer (NASDAQ:AAPL). The iPod practically reinvented Apple, and sales sparked interest in its other products. TurboChef does offer three versions of its high-speed ovens, but I wouldn't dare label it a multiproduct company until I see something else like a high-speed dryer offered.

So be careful with companies like TurboChef that focus on one nonessential product. Your portfolio could get cooked.

Our newsletters include a variety of recommended stocks: Taser is a Motley Fool Rule Breakers selection; TiVo and Krispy Kreme Doughnuts are Stock Advisor picks. Click here to take a look.

Fool contributor Dean Paton wakes up at the crack of noon every day to check his stocks before going back to sleep. He does not own any of the shares mentioned.

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