TurboPrint is a closed source printer driver system for Linux, AmigaOS and MorphOS. It supports a number of printers that don't yet have a free driver, and fuller printer functionality on some printer models. In recent versions, it integrates with the CUPS printing system.
(in German) Michael Kofler, Jetzt lerne ich Linux im Büro: Office-Aufgaben einfach und sicher unter Linux meistern, Pearson Education, 2004, ISBN3-8272-6782-X, p. 95