From STD Utility
STDU XML Editor is a lightweight editor of XML documents. This editor is very simple to use. The XML document is represent as tree, and you don't need to know anything about markups language, for edit documents in our editor.
Handy features include:
* Modern tabbed document interface.
* Good performance on large XML documents.
* Cut/copy/paste with full namespace support.
* Drag/drop support for easy manipulation of the tree.
* Infinite undo/redo for all edit operations.
* Portable version for your flash-drive.