As investors, we are always on the lookout for interesting new stock ideas. In fact, many of us spend countless hours of research in pursuit of revolutionary, game-changing companies, those with the potential to have a dramatic impact on their market — and on the portfolios of their shareholders.

However, sometimes the simplest of ideas can be the most influential and profitable. In other words, innovative companies aren't always Silicon Valley start-ups known only to savvy venture capitalists. Sometimes they can be found right under our noses in the most mundane places.

With that in mind, Market Advisor editor Paul Tracy took readers on a behind-the-scenes tour of popular retailers like Wal-Mart in his February 2005 newsletter. Almost everyone is familiar with the constant beeps echoing throughout these stores, as cashiers constantly scan the barcodes on products that are rung up at the cash register.

When the barcode was first put into use in 1972, it changed the retail world forever. If you think checkout lines are slow now, just imagine what it was like when the price of each item had to be entered manually. But now, we are on the threshold of an entirely new era. One where an entire shopping cart overflowing with items can be tallied up instantaneously just by walking under a scanner.

The technology that makes this possible, radio frequency identification (RFID), is already in use today and will soon become much more widespread. RFID will not only lead to dramatic improvements in efficiency, but will also help retailers better manage their inventory and save billions every year in stolen merchandise. You've probably already seen this theft-detection technology at work at store entrances — it beeps whenever a tagged item is taken from the premises illegally.

Already, Wal-Mart has mandated that its vendors become compliant with RFID technology, and the U.S. Department of Defense is requiring all 50,000 of its suppliers to do the same. And the retail world could be just the beginning; the technology has plenty of other applications, from casino chips to E-ZPass tags for electronic toll booths.

At the time, Paul scrutinized each of the players in this nascent industry and settled on Checkpoint Systems (NYSE: CKP, $27.75), an industry leader boasting longstanding relationships with large retailers like Albertsons and Kohl's (NYSE: KSS). Today, Checkpoint has more than a million RF devices installed worldwide, and the firm just enjoyed its most profitable year ever, with earnings soaring +60% on over $800 million in revenues.

Meanwhile, the shares have been following a similar trajectory, climbing from $16.96 to Friday's close of $27.73 — a gain of more than +60%.

In this month's newsletter, Paul zooms in on another exciting company benefiting from an earth-shaking new technology. The firm is a leader in the biometrics field, supplying next-generation facial-recognition devices. Just as RFID is supplanting the barcode, biometrics are replacing outdated fingerprints, and this month's featured pick already has a backlog of orders and is considered the front-runner for up to $750 million in new contracts.

To read Paul's complete profile of this exciting company, available only to subscribers, we invite you to take a no-obligation free trial of Market Advisor. Please visit the following link to learn more.