Seeking Firefox plug-in for HTML authoring

Do you have a question? Post it now! No Registration Necessary.  Now with pictures!

I'm looking for the easiest way to author HTML document that presents
pages similar to, say simple Microsoft Word docs.

One example I'm playing with is RedCloth + Textile, which is pretty
good.  I've heard there's some Firefox plug-in that provides somewhat
similar functionality.  Do any URLs come to mind?

Thanks in advance,

Site Timeline