Has anyone created a matrix paned widget?

[Robert Kallal <Robert Kallal ustc vlsi COM>]

Hi all,

I was wondering if anyone has created a matrix paned widget in which you 
can add H or V panes that overlay each other.  The idea I was having was 
to have something like this:


          |
   C(0,1) | C(1,1)
          |
   -------+-------#
          |
   C(x,y) | C(1,0)
          #


Where C(x,y) defines a container space and there could be any number of H 
or V pane splitters.


Robert Kallal