Function to insert the in-use template and page id into the document head as a comment. Aids in debugging.

md_insert_template_info

	add_action( 'wp_head', 'md_insert_template_info');
	function md_insert_template_info() {
		global $template;  
		global $post;

		// get the path part
		$url = parse_url($template, PHP_URL_PATH);
	
		// split on /
		$surl = explode('/',$url);
	
		// template file is the last one
		$tmpl = $surl[count($surl)-1];
	
		// insert as commment
		$out = 	"\n<!-- ----------------------------------------------------------\n\n" .
			   	"\tTemplate: $tmpl\n" . 
			   	"\t    Path: $url\n" . 
			   	"\t Page ID: " . 
			   	get_the_ID() . 
			   	"\n\n" . 
			   	"-------------------------------------------------------------- -->\n\n";
		echo $out;
	}