<html>
<head>
<title>Enviar formulario al pulsar un enlace</title>
<script>
function enviar_formulario(){
document.formulario1.submit()
}
</script>
</head>
<body>
<form action="pagina_destino.php" method=post name="formulario1">
<input name="nombre" onkeypress="if (event.keyCode == 13) enviar_formulario()"/>
</form>
</body>
</html>