Codice PHP:
<HTML>
<
BODY onLoad="res();">
<
SCRIPT language="Javascript1.2">
function 
res()
{

var 
x=screen.width;
var 
y=screen.height;
var 
hx=x/2;
var 
hy=y/2;
var 
a=800;  
var 
b=600;  
var 
ha=a/2;
var 
hb=b/2;
var 
dx=hx-ha;
var 
dy=(hy-hb)-20;
var 
param="width="+a+",height="+b+",left="+dx+",top="+dy+",screenX="+dx+",screenY="+dy;
window.open("http://www.google.com/","Popup",param);
}
</SCRIPT></BODY></HTML>