Restructured Text and Trac
Recently I've come to love restructured text. It excels at everything it tries to, without being overcomplicated. Our heavy reliance on subversion for version control, sharing and merging means that we need a non-binary format where possible for documentation; that combined with the many tools to convert it to other formats (including our own to convert from ReST to PDF which I promise we will publish soon) and suddenly my previous reliance on GUI-heavy word processors seems strangely unnecessary and over the top.
Another tool we simply couldn't do without is Trac. Once you get the hang of it it literally adds another project member to your team - it really is that powerful. So far we've only found one drawback, which is that the wiki uses a bespoke markup for formatting.
"What we want," thought Doug and I, "is a way to combine the power of Trac with the power of ReST, so that we can have our live documentation in the repository in sync with the wiki"
Obviously we aren't the only people to have had that thought. Like all the best ideas it combines two very powerful things and makes them all the more powerful. That and it's a piece of cake to use. Doc publishing for the lazy Trac user. Like the man says, "using it is adopting it." It really is that simple.