XML Editor
From openSUSE
You can use any text editor for editing XML files. For better results, you sometimes can install an add-on for your text editor or use dedicated XML editor like conglomerate.
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GNU Emacs
Install the psgml add-on if you want to turn Emacs into an XML editor. Restart Emacs and visit an XML file. Use the SGML menu to insert XML tags.
psgml is part of openSUSE. Find more info about GNU Emacs at http://www.emacswiki.org and about Emacs as an XML editor at http://www.emacswiki.org/cgi-bin/emacs-en?CategoryXML

