X3D is the open-standard format for 3D graphics scenes on the Web.
XML Schema for questionnaires and PDF questionnaire generator
XML text markup for ancient documents
Parse and decode METAR, TAF, SYNOP, BUOY, AMDAR and write data as XML
eXist-db is a feature rich Open Source native XML database
CAM XML Editor for XML+JSON+Hibernate+SQL Open-XDX sponsored by Oracle
Digital edition visualization software
DocBook Publishing Made Easy
professional open source software for LCA
xslet project provides some XSL libraries and applets.
GeoNetwork for AU/NZ users
A free universal Braille Transcriber