XML Copy Editor - XML Copy Editor is a fast, free, validating XML editor.
showFoto - ShowFoto is the standalone image editor of the digiKam project.
Oxygen XML Editor - Oxygen XML Editor provides a comprehensive suite of XML authoring and development tools.
PixBuilder - Free Photo Editing Software for PC
Liquid Studio - XML Tools Provider: XML Studio - Graphical XML Schema Editor.
PhotoDemon - Lightweight portable BSD licensed photo editor for Windows focused on performance and usability.