<html>
  <script langugage=javascript>
  <!--
  var i=12;
  document.write("<input type=hidden name=illboy value="+i);
  -->
  </script>
  <body>
<input type="button" onclick="window.open('2.htm')">
</body>
<html>2.htm:
<script language="javascript">
<!--
document.write("The var is:"+window.opener.illboy.value);
-->
</script>