I'm the maintainer of Prawn, and yeah, it'd be nice to see this.   Jamis Buck tried this with prawn-format, but after a while we dropped support for it because it fell behind our core library and started breaking (Jamis had since moved on to other things).<p>In order for this to happen, what we really need is a solid box model.  Since we don't have that yet, it's a very hard problem.  If someone wanted to pay me to work on it full time for a year, I could get it built.<p>But failing that, we'll have to wait a good deal of time for this, unless someone else finds a large chunk of dedicated time for it.<p>Until then, Flying Saucer is the way to go if you can't afford PrinceXML price tag.