CUPS is a wonderful printing system that uses the emerging IPP protocol. The only drawback is that there is quite no free driver available to print with. CUPS-drivers address this issue by providing a generic printer driver using GNU GhostScript. Not many printers are supported to date, but all is in place to support as many printers as GS can. If GS supports your printer, then CUPS-drivers will support it as well. Help and feedback are welcomed.
xmlroff is a fast, multilingual, multi-platform XSL formatter that transforms XSL-FO documents (or any XML with an appropriate XSL stylesheet) into PDF or PostScript. It aims to excel at DocBook formatting, and it integrates easily with other programs and with scripting languages.
The X Printing Panel (XPP) is a tool for choosing the desired printer out of a list of all printers available under CUPS and for setting printer options by an easy-to-use GUI. One simply calls the program instead of the usual utilities (lpr or lp) at the command line or out of applications.