Backing up only package configuration files ?

[John Affleck]

Is there an easy way to extract a list of all of the .deb marked
configuration files in the system (or for an individual package). 
Some minimum of awk/perl magic would allow me to grab all of the files
between:

Conffiles:
 /etc/Muttrc cc4a19334317d9f8fab55cd9d6f270ad
Description:

..to get '/etc/Muttrc' for example, but I'm wondering if there's an
easy way to do it for an entire system.  I figured 
'dpkg-query --showformat' might do it, but I was unable to make it
do anything meaningful.

I'd like to be able to do something like:
'dpkg-findconffiles | cpio -o | gzip > conffiles.cpio.gz'
for example..