function openPopup (c) {
	w = 700;
	h = 500;
	wleft = (screen.width - w) / 2;
	wtop = (screen.height - h) / 2;
	var win = window.open(c,
		'popup',
		'width=' + w + ', height=' + h + ', ' +
		'left=' + wleft + ', top=' + wtop + ', ' +
		'location=no, menubar=no, ' +
		'status=no, toolbar=no, scrollbars=no, resizable=no');
	// Just in case width and height are ignored
	win.resizeTo(w, h);
	// Just in case left and top are ignored
	win.moveTo(wleft, wtop);
	win.focus();
}