gistfile1.js

    function valueForKeyRecurse(object, chunks) {
        var bit = chunks.shift(), val;
        if (bit in object) {
            return chunks.length
                ? valueForKeyRecurse(object[bit], chunks)
                : object[bit];
        } else {
            var getter = object['get' + bit.charAt(0).toUpperCase() + bit.substring(1)];
            if (typeof getter == 'function') {
                return chunks.length
                    ? valueForKeyRecurse(getter.call(object), chunks)
                    : getter.call(object);
            }
        }
        return null;
    }
    
    function valueForKey(object, key) {
        if (key.indexOf('.') > 0) {
            return valueForKeyRecurse(object, key.split('.'));
        } else {
            return valueForKeyRecurse(object, [key]);
        }
    }

gistfile2.js

    <script type='text/javascript'>
      var obj = {
        'foo': {
          'bar': {
            'getBaz': function() { return 100; }
          }
        }
      };
      
      alert(valueForKey(obj, 'foo.bar.baz'))
      // => 100
    </script>

Allows a JS object to be queried by path, supporting either object properties or getter functions. Similar to Key-Value coding in Cocoa.