FYI, QuickBook already has the reverse-lit feature. It lets you "import" code snippets from actual code. Rene and I are using it right now to great effect.
I have to say, as a non-CS person, I'm finding it hard to even keep track of the differences between DocBook, BoostBook, and QuickBook, much less figure out how to accomplish anything with them... Just as a side note, given that documentation is already generally regarded as one of the most painful parts of library development, I think it would be a good idea for Boost to standardize on one system or another and then provide a good tutorial on how to use it... For example, after browsing all the QuickBook documentation I could find, I still have no idea how to implement the code snippet import feature you described; furthermore, as far as I can tell, there is no .qbk source in Boost (from recent CVS-HEAD) that I could use to try to emulate your Spirit documentation (assuming that is the documentation that uses this reverse-lit import, which I can't know a priori). Finally, while there appears to be some way to have DocBook output LaTeX, it isn't clear to me that there is any way to have it parse and process LaTeX source in, for example, the way that Doxygen does so that you can get images of typeset equations in the HTML output. Maybe it's possible, but it is certainly far from obvious, and the amount of time I would have to invest learning a completely new system hardly seems to justify the potential benefit. Anyway, sorry for the rant - it just doesn't seem like this should be this painful... Matthias