A Ruby-powered Rapid Document Authoring Framework. With Glyph, you can manage your documents tidily in projects and generate deliverables in different formats such as HTML or PDF (through Prince).

Use HTML+CSS to generate PDFs using wkhtmltopdf

Docsplit is a command-line utility and Ruby library for splitting apart documents into their component parts: searchable UTF-8 plain text, page images or thumbnails in any format, PDFs, single pages, and document metadata (title, author, number of pages...)

A framework for creating e-books from Markdown/Textile text markup using Ruby. Using the Prince PDF generator, you'll be able to get high quality PDFs.

PDF generation library