pdq is a straightforward, flexible print subsystem.
It has the following features:
o Modular driver and interface support.
o Jobs can be monitored through completion.
o Job status can be checked after completion.
o Users can only print files of declared types.
o Users can define their own printers.
o Multitasking, with no queues to get clogged.
o Scripts can be embedded in the rc files.
o Custom command-line options.
o Root privileges not required.

WWW: http://pdq.sourceforge.net/