fengshui is a rack diagram generator. It takes XML files that describe the layout of the rack and generates PNG diagrams of the rack. It uses the cairo graphics library for rendering, so in theory PostScript and PDF output is also possible.
A GTK editing tool is also in development.
fengshui is free software, licensed under the GPL.
You can download a snapshot tarball from here.
The latest version of the source code is kept in bazaar:
bzr get http://repo.spacepants.org/fengshui/mainline>
Send any patches or suggestions to Jamie Wilkinson