That's nice. I was in the same line of work. Started from building our own XML parser, when there were none available yet. Later I developed this fun XSLT that generated a fullblown Forms UI based on an XML and/or XML Schema which we used in a custom CMS. Then with XSL-FO and Quark XPress we generated user manuals and product catalogues from that. The XSLT was surprisingly fast for the time, and given the transformations it needed to do.