#!/usr/bin/perl -w
use strict;
use Tk;
my $mw = tkinit;
$mw->withdraw();
my $i=0;
my $k=0;
while (1) {

        my $notification = $mw->Toplevel();
        $notification->geometry("+$i+$k");
        $i+=10;
        $k+=5;
        $notification->protocol('WM_DELETE_WINDOW' => sub { $notification->withdraw;  });
        $notification->Label(
            -text       => 'Your message displayed here.',
            -height     => 5
        )->pack;
        $notification->withdraw;              
        $notification->deiconify;
        $notification->raise;
        $notification->update();
        $mw->after(5000);
}