Yeah, I think I saw a Japh like that, where you couldn't get the mouse over the window without it jumping. Something like:

#!/usr/bin/perl
use strict;
use Tk;
my $mw = new MainWindow();
$mw->geometry("100x100+100+100");

my $label1 = $mw->Label(-text => "Catch Me Fool", -bg => 'cyan')->
pack(-fill => 'both', -expand => 1,);

#put stuff here
$mw->bind("<Enter>",sub {
 my $x = int rand 600;
 my $y = int rand 600;
 $mw->geometry("+$x+$y");
 });

MainLoop;
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