I use HTML-Kit on windows. One reason is because of its WYSIWYG prototype pad. Just click on the tools tab and click the pencil icon to the far right. Sadly enough I'm one of those people waiting for what seems to be vaporware First Page 3. I also like the new Boa Constructor v0.13 CVS version. I'm trying to figure out how to use 0.13 of Boa with Zope. -James
For Windows I use HTML-Kit (http://www.chami.com/html-kit/) it has a nice FTP interface, doesn't mess up dtml, has lots of plugins, is very configurable, oh yeah, and free. It is NOT WYSIWYG, but I don't want it either, that is my preference. It does syntax highlighting, code completion, allows you to save templates and snippets, and integrates nicely with html tidy, browsers and top-style (for CSS - http://www.bradsoft.com/topstyle/index.asp). Did I mention it's free?
Anyway, that's what I use, enjoy!