Most Tk widgets, which take an itemtype, can take an itemtype of "window", which you can load with whatever you want.

#!/usr/bin/perl -w
use strict;
use Tk;
use Tk::TixGrid;

my $g;
my $mw = Tk::MainWindow->new();
$mw->optionAdd('*selectBackground' => 'lightblue');
MakeGrid($mw);
MainLoop;


sub MakeGrid
  {
    my ($w) = @_;

    $g = $w->Scrolled('TixGrid');

    $g->pack(qw/-expand yes -fill both -padx 3 -pady 3/);

    $g->size(qw/col default -size 10char/);
    $g->size(qw/row default -size 2.1char -pad0 3/);

    for my $x (0..9)
      {
    for my $y (0..9)
          {
        my $window = $g->Button( -text=> int rand 100,
                       -command=> sub{print "$x $y\n"}
        
        );
            $g->set($x,$y, -itemtype=>'window',-window=> $window );
      }
      }
  }

__END__
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