Erik Moeller wrote:
for exporting MediaWiki pages as PDF files, and improving document management for documents consisting of multiple pages. [...] c) Create a "PDF basket" UI which makes it possible to compile a PDF from multiple pages easily (and rearrange the pages in a hierarchy).
Things to throw into this basket are Wikisource and Wikibooks. These projects currently consist of thousands of "pages", but there is no way to separate a "book" (or title or volume) from the rest of the site. For example, at download.wikimedia.org I can download the entire French Wikisource in XML, but I cannot download the XML (or PDF) for just one of the books there.
If I'm lucky, all wiki pages (facsimile pages or chapters) that belong to one book are subpages of a single page, or all have page names that begin with a common prefix, but the current Mediawiki software doesn't help in maintaining this integrity. Clicking around to manually fill a PDF basket would be a nightmare.
Of course, for a Wikisource book with scanned images, I'd like these printed in the PDF. But the OCR text would be used for searching through the PDF.
As far as I know, the ProofreadPage extension (the Page: namespace) doesn't support a grouping or table of contents of all pages belonging to a book. This would be a useful next step.
The resulting structures could potentially also be stored as wikitext, using a new <structure> extension tag, so that they can be used both by individuals compiling PDFs for personal use, and by groups collaborating on complex documents.
This could be it.