I always thought that free XML editors (and some commercial ones) were limited to two display modes:

• A tag view, which essentially displays your document as-is, but with color-coding of tags and other kinds of markup. When XML first became popular, the more powerful programmer's editors added an XML mode that did this to their list of modes for various programming languages. A proper XML editor also enforces dynamic validation, so that when you enter the command to insert an element the editor only offers you a choice of valid elements for the cursor position.

• A tree view, which is easy to create with typical GUI widgets, and can be handy for transactional XML data (a.k.a. data-oriented XML) but is lame for narrative (a.k.a. "document-oriented") XML—who wants to see their paragraph shown as a node of a tree with text node children that have a an emphasis element as one of their siblings?

A word processor-like view, which distinguishes between block and inline elements and displays each according to some hopefully straightforward specification, seemed like the province of more expensive editors such as Arbortext and XMetaL, but I recently discovered Pixware's XMLmind. Their free "Personal Edition" is available for both Windows machines and Macs. It uses CSS stylesheets to style the documents that you create as you edit them. Pixware offers a Professional Edition for $250 that has more features such as on-the-fly spell checking, but the free one still has a spell checker (with a wide choice of dictionaries, because it's from a French company), and comes with CSS stylesheets for several popular document types.

It worked just fine with my own HTML CSS stylesheet that I use for writing things like this. I might even suggest that someone uninterested in XML but who wants to learn about web page creation use it with the XHTML DTD and CSS. You can't beat the Personal Edition's price.

I'll continue to use Emacs, because I do want to see the markup, and I have too much affection for nxml mode, all the other off-the-shelf Emacs features, and the ones that I've developed myself. To proofread, I add an xml-stylesheet processing instruction and then view the document in Firefox. For people who are interested (or have friends or clients interested) in interactive editing of styled XML documents without spending any money, though, XML Mind is worth a good look.