smart redirects from 404 pages.

gistfile1.js

<script>
$.getJSON('/_/js/url_mapper.json', function(data) {
	path = location.pathname.split("/") ;
	if ( path[1] == "post" ){
		id = path[2];
		if ( data[id] ) {
			$('#msg_en').html("The page you are looking has probably moved to \<a href=\"" + data[id] + "\"\>" + data[id] + "\</a\>.") ;
		}
	}
});

// See http://blog.vrypan.net/2012/11/23/dynamic-404-for-static-blogs/

</script>