Xps
From NDesk
This is an implementation of XPS (XML Paper Specification), a fixed-layout document format. It's not yet complete but manages to render many documents.
It works by targeting Cairo, a 2D graphics library with support for multiple output devices. The imaging models are fairly similar so lossless conversions to targets like PDF should be possible.
NDesk Xps is capable of taking an xps file and processing it entirely in memory, including support for loading and de-obfuscating embedded fonts and subsetting them (using Cairo) to the target surface. This means that text can maintain its typographic qualities throughout conversion without rasterisation.
Xps
Download
git-clone git://git.ndesk.org/pub/scm/ndesk-xps
Usage
mono loader.exe Document.xps
This produces Document.pdf.