Two new ETTK packages are now available: Compound XML Document Editor and XML Forms Generator.
A compound document combines XML markup from several namespaces into a single physical document. A number of standards exist, and continue to be developed, that are descriptions of XML markup within a single namespace. XHTML, XForms, XML Events, Scalable Vector Graphics (SVG), VoiceXML, and MathML are a handful of prominent examples of such standards, each having its own namespace.
To authors of content, each of these standards is useful and important. However, it is the combination of elements of any number of these standards that lends true flexibility and power. A document may exist to be displayed within a Web browser, to display an input form, with a scalable graphic and a bit of mathematical notation, all on the same page. XHTML, XForms, SVG, and MathML, respectively, serve these needs, and would therefore be combined into a single multi-namespace, or compound document.
Recently, the Opera and Firefox browser teams announced plans to add native SVG support in their upcoming browsers. I think as more and more browsers natively support SVG, XFORMs, MathML, etc., Compound documents will be used extensively.