FingerPrint is a new Mac OS X application from Collobos Software that enables AirPrint printing for many OS X printers. AirPrint is Apple's new wireless printing technology for iOS devices. It works over Bonjour, Apple's version of zero configuration networking, allowing devices and services to communicate with each other on local area networks.
As originally planned, AirPrint was supposed to provide printing to shared OS X printers and to a small group of HP printers that support HP's ePrint mobile printing service. However, this feature was disabled in the final Mac OS X 10.6.5 release, and AirPrint now only supports the HP printers. FingerPrint brings the capability back to shared printers without having to resort to Terminal commands.
The $7.99 application works by browsing for Bonjour printer services. When it finds them, it re-advertises the printers adding a special field to the Bonjour data that indicates AirPrint compliance. By projecting that compliance information, your iOS devices are able to detect and then write to those printers using standard OS X protocols.
Update: See our exclusive first look at Ecamm's competitive offering, Printopia for Mac