Hello,
I recently came up with a new idea for an archive format that I call
"recursive archival" or "inverse tar". I created a simple
implementation of this in Ruby called Rock. (If you like you can read
about it here: http://rock.rubyforge.org/overview.html). Originally I
had some additional ideas about using the format for Ruby packages.
But on further consideration, I think the idea is too "fundamental" to
justify such a project and really would make more sense as simply an
additional feature of tar itself.