easy:
codice:
<html>
<head>

<script language="Javascript">
<!--
function cambia(campo)
{
	var e = document.getElementById("etichetta");
	e.innerHTML = campo.value;
	
	return 0;
}
//-->
</script>

</head>
<body>

<form>
<select name="sel" onChange="cambia(this);">
	<option selected="true"></option>
	<option>valore 1</option>
	<option>valore 2</option>
	<option>valore 3</option>
</select>
</form>

<div id="etichetta"></div>

</body>
</html>