XML

XMLtoPDF

XMLHttpRequest?: http://jibbering.com/2002/4/httprequest.2004.html

XMLCatalogs

<!DOCTYPE reference http://www.blooberry.com/indexdot/html/tagpages/d/doctype.htm

Craig's post on resolving Struts DTDs locally: http://marc.theaimsgroup.com/?l=struts-user&m=107842475723945

StateChartXML in the Jakarta Commons Sandbox

XFire