Interactivity Outside of Map

Show data from UTFGrid in other elements
<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
<title>Interactivity Outside of Map</title>
  <meta name='viewport' content='width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no' />
  <script src='//api.tiles.mapbox.com/mapbox.js/v1.4.0/mapbox.js'></script>
  <link href='//api.tiles.mapbox.com/mapbox.js/v1.4.0/mapbox.css' rel='stylesheet' />
  <!--[if lte IE 8]>
    <link href='//api.tiles.mapbox.com/mapbox.js/v1.4.0/mapbox.ie.css' rel='stylesheet'>
  <![endif]-->
  <style>
    body { margin:0; padding:0; }
    #map { position:absolute; top:0; bottom:0; width:100%; }
  </style>
</head>
<body>
<style>
#map {
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    right: 100px;
}

#count {
    position: absolute;
    right: 0px;
    width: 100px;
    top: 0px;
    bottom: 0px;
    font-size: 40px;
    z-index: 99;
    color: #fff;
    padding: 10px;
    background: #000;
}
</style>
<div id='map'></div>
<div id='count'></div>
<script>
var map = L.mapbox.map('map', 'examples.map-8ced9urs', {gridControl: false});

map.gridLayer
    .on('mousemove',function(o) {
        document.getElementById('count').innerHTML = (o.data && o.data.count) || '';
    }).on('mouseout', function(o) {
        document.getElementById('count').innerHTML = '';
    });
</script>
The code and documentation to mapbox.js is hosted on GitHub where you can contribute changes and improvements.