Zoom Tan Inc. of Naples, Fla., doesn't accept cash or checks — and its customers are often too scantily clad to be carrying them anyway.

For those customers who don't want to carry cards either, the chain of 27 privately owned tanning salons in Florida and New York this year began using biometric technology from Redwood City, Calif.-based DigitalPersona Inc.

Despite much early buzz, biometric payment systems failed to take off as hoped, and industry interest waned after the 2007 bankruptcy of Solidus Networks Inc., a San Francisco company that did business as Pay By Touch.

But as hackers continue to erode the defenses of conventional payment systems, biometric systems may be due for a comeback.

"We have every reason to expect to see more use of biometrics at the point of sale as merchants begin taking another look at the security and convenience factor it provides for payments," says Gary Oberman, DigitalPersona's business development director.

The technology adds "a great deal of efficiency" to the Zoom Tan's salons, which typically have only one staff member, says Scott Bogdan, Zoom Tan director of operations.

"By accepting only cards and getting customers to register for biometrics, we save a lot of time and money," he says.

The fingerprint-check system also prevents fraud from friends and family members that might try to use a customer's prepaid tanning membership, Bogdan says.

Zoom Tan pays a card-not-present rate to its acquirer to process the transactions, Bogdan says. Card data is encrypted so the information is never exposed, he says.

Customers are not required to register their fingerprints, but "once they understand how it works, a light bulb goes off and they realize it's a lot easier than getting their card out every time they come for a tan," he says.

DigitalPersona's technology captures an image of a customer's fingerprint, extracting "40-50 unique features," then encrypts it and stores it as a template used to match against the customer's actual finger on a point-of-sale reader, the company says.

Zoom Tan's use of the fingerprint technology suggests biometrics for payments is not altogether dead.

DigitalPersona for years has strived to develop interest in biometrics at the retail level.

One of its largest implementations is Mexico's Banco Azteca, which widely uses biometric technology for account access.

"Everyone is talking about mobile payments, but biometrics serve some of the same purposes," Oberman says. "It's secure, it's fast and biometrics could even play a role in securing mobile payments."