Something

<HTML>
<HEAD>
<TITLE>Stock List</TITLE>
<SCRIPT LANGUAGE="JavaScript">
<!--

function pick() {
theForm = document.forms['address'];

  if (window.opener && !window.opener.closed)
     for (i = 0; i < list.length; i++){
                
		if (theForm.elements['list'+i].checked == true){
			checked_list += theForm.elements['list'+i].value;
  		}
		window.opener.document.stockForm.stockBox.value = checked_list;
		window.close();
}


// -->
</SCRIPT>
</HEAD>
<BODY>
<form name="address" action="" method="post">
<input type="checkbox" name="list" value="wootwoot">wootwoot
<input type="checkbox" name="list" value="micheal">micheal 
<input type="submit" name="submit" value="submit" onclick="pick()">
</form>
</BODY>
</HTML>