Here at the Fool, we think "watch lists" are a great idea. For those who aren't familiar with the concept, that means tracking a list of stocks that you really like but either don't have the resources to invest in today, or would like to buy at a cheaper price. The trick, though, is to actually remember to pull the trigger and buy a good stock every once in a while. Had I remembered this, I might have joined in some of the fun in EuronetWorldwide (NASDAQ:EEFT) over the past couple of years.

As a provider of "top up" services for prepaid cell phone minutes and an operator of the largest independent ATM network in Europe, Euronet is an electronic commerce company that is actually making money hand over fist.

In business for 10 years, Euronet has grown its revenue from roughly $50 million in 2000 to over $380 million in 2004. For the fourth quarter, Euronet reported that sales grew 61% and operating income more than doubled.

Euronet ended the quarter with over 5,700 ATMs in service across Europe and India and processed more than twice as many ATM transactions in the fourth quarter of 2004 as in the prior year. While Western Europe may not have as much room for growth as in the past, Euronet still has considerable opportunities in Eastern Europe, India, and other areas as well.

Prepaid cell phone "top up" processing was also strong in the fourth quarter. Unlike the United States, many Europeans prefer to use prepaid cell minutes, and prepaid business is more than 50% of cell phone business in many areas of Europe. This is the largest business segment for Euronet, and revenue grew 71% for the fourth quarter. Although Euronet is already the largest prepaid processor in Europe, there is still room to expand throughout the continent and into other regions of the world as well.

While I don't imagine Warren Buffett's Berkshire Hathaway will be snapping up Euronet shares any time soon, the stock is not unreasonably priced relative to its growth and potential. The company didn't provide cash flow information, but the enterprise value-to-free cash flow ratio looks to be around 20 or so, and the trailing P/E is about 42. Those numbers aren't out of line, especially considering that the company hasn't even begun to reap the potential in markets like Russia, China, or Brazil.

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Fool contributor Stephen Simpson, CFA, has no ownership interest in any stocks mentioned but really wishes he did.