All of our writers and editors use Microsoft Word for document creation and a lot of what they create ends up on the Web. Is there a good offline editor with a flavor similar to Word that they could use to create their documents. Styling of the content should not be a concern, only producing semantic HTML (most documents they create could be done using only header and paragraph tags for instance). They have tried CKEditor and TinyMCE but it is still too foreign for them and it is online so they don't trust it not to lose their work.
Notepad++ is a good editor for almost anything. http://notepad-plus.sourceforge.net/
Have you taken a look at OpenOffice and its XHTML export? From what little I've toyed around with it, it produces very clean code - turns OpenOffice headings into HTML headings and so on. It even exports images as inline "data" URLs.