Wikipedia
The CueCat, styled :CueCat with a leading colon, is a cat-shaped handheld barcode reader that was released in 2000 by the now-defunct Digital Convergence Corporation. The CueCat enabled a user to open a link to an Internet URL by scanning a barcode — called a "cue" by Digital Convergence — appearing in an article or catalog or on some other printed matter. In this way, a user could be directed to a web page containing related information without having to enter a URL. The company asserted that the ability of the device to direct users to a specific URL, rather than a domain name, was valuable. In addition, television broadcasters could use an audio tone in programs or commercials that, if a TV was connected to a computer via an audio cable, acted as a web address shortcut.
The CueCat connected to computers using the PS/2 keyboard port and USB, and communicated to desktop "CRQ" software running on Windows 32-bit and Mac OS 9 operating systems. Users of this software were required to register with their ZIP code, gender, and email address. This registration process enabled the device to deliver relevant content to a single or multiple users in a household.
Codes can no longer be generated for the device. However, third-party software can decode the lightweight encryption in the device.