// Special thanx to Moshu, http://moshu.devnull.ro
function popup(file, width, height) {
var winl = (screen.width - width) / 2;
var wint = (screen.height - height) / 2;
windowprops = "left="+winl+",top="+wint+",width="+width+",height="+height+",scrollbars=0";
window.open(file, 'popup', windowprops);
}