It occurred to me that some might find it congenial to be able to download a .WAR file that drops into Tomcat or Jetty and provides a REST (or, perhaps, SOAP?) web service that runs FOP. Using Apache CXF, this would be a rather straightforward exercise. This would make it easier to set up FOP once, with whatever configuration appeals to you, and then use it on your network.
I could bang such a thing together using Apache CXF if you all, who have a much better sense of how FOP gets used than I do, think it's worthwhile. It would be an independent build from the main fop tree, and, warning, it would get built with Maven.