"dual" files

Hello, 

recently i was thinking about a generic file viewer/reader for GNOME.
Eog does this job for images but it would be really cool IMHO to be
able to view all kinds of files even though you might not have the
actual file-producing application installed.

Two possible approaches came to my mind:

What about including say an svg version within each document (or do
it optionally). The XML nature of the gnumeric and abiword file
format should allow for that pretty easily (in theory at least :-)
This way might overlap with the plans for svg based gnome-office
embedding. Of course the resulting document files would be a bit
"heavier".

A second possibility might be to somewhow split out printing code and
create a set of "print drivers" for commonly used file formats and
use them within the viewer and the respective application. An
intermediary solution could be the libegg way of including sources.

With the gnome-office programs' excellent reputation of file-format
support a broad range of different file types could be supported.

Thanks for any comment, 
Rob