WordPress AJAX response codes using status_header

I’m constantly searching around for the cleanest and most “WordPress way” to do things vs. re-inventing the wheel.  One function that helps write cleaner AJAX call handlers is status_header(), to inform the caller when things go wrong:

add_action( 'wp_ajax_myajaxaction', 'my_ajax_handler' );

function my_ajax_handler() {
    if ( ! empty($_POST) and check_ajax_referer( 'mynonce', 'nonce' ) ) {

        if ( things_go_wrong ) {
            status_header( 500 );
            echo "some informative message or code";

        // ...

and in the javascript using success and failure functions rather than deconstructing response text:

var nonce = jQuery("input#nonce").val();

   type: "POST",
   url: ajaxurl,
   data: {
	   name: encodeURIComponent(tabName),
	   id: tabId,
	   mynonce: nonce,
	   action: 'myajaxaction'
	 success: function(msg) {
               // Handle a successful call
	 error: function(v,msg) {
            // Handle the error, with the text in msg

You could also output the headers manually, but this gives a nice clean way to do it.