http://mines.mouldwarp.com/2011/06/time-buffered-wui-update-javascript.html

time_buffer.js

var _timeBuffer = (function() {
  var tos = {};
  return function(act, func, min, max) {
    function _doFunc() {
      var to = tos[act]; tos[act] = null;
      if (to) { clearTimeout(to.max); clearTimeout(to.min); }
      func();
    }
    var to = tos[act];
    if (to) { clearTimeout(to.min) }
    else { tos[act] = to = { max: setTimeout(_doFunc, max) } }
    to.min = setTimeout(_doFunc, min);
  };
})();