function aaben(bill,bredde,hoejde){
var venstrePos =Math.round(screen.width - bredde)/2;
var topPos =Math.round(screen.height - hoejde)/2;

window.open( bill,'','width='+bredde+',height='+hoejde+',top='+topPos+',left='+venstrePos+'toolbar=no,location=no,directories=no,status=no,resizable=no');
}