That's because bar code-based time and attendance systems have a big loophole: buddy punching. Johnny Come Lately, delayed on his way to work, can ask fellow employee Bobby Buddy to swipe Lately's bar-coded employee badge through the time clock. The time clock will faithfully record Lately's attendance before he arrives, and the employer will pay Lately for time that he didn't work.
Biometric time systems eliminate buddy punching because they are inextricably linked to the employee, not to a token such as an employee badge or a time card.
I looked at the WaspTime Biometric Time and Attendance System ($999 list price), an integrated bundle from Wasp Barcode that includes a biometric time clock, WaspTime Software Suite time attendance software for Windows, an ethernet cable, and a AC power adapter.
The time clock is a wall-mountable box with a laser optical fingerprint scanner, a monochrome backlit four-line LCD, and a numeric keypad with five menu-control buttons. The clock can be directly hooked up to a PC using a serial port, USB connection, or (the way I tested it) connected to a network via ethernet.