var l = new Array;
var b = new Array;
l[0] = "http://www.madtec.net/";
b[0] = "/bas/banner/madtec3.gif";
l[1] = "http://www.bas-hk.com/";
b[1] = "/bas/banner/bas.gif";

var ran = l.length;
var randnum = Math.random();
var no = Math.round((ran - 1) * randnum);
document.write("<a href='" + l[no] + "' target='new'><img src='" + b[no] + "' border=0 valign=top></a>");