function initMoving(target, position, topLimit, btmLimit) {
 if (!target)
  return false;
 var obj = target;
 var initTop = position;
 var bottomLimit = Math.max(document.documentElement.scrollHeight, document.body.scrollHeight) - btmLimit - obj.offsetHeight;
 var top = initTop;
 obj.style.position = 'absolute';
 if (typeof(window.pageYOffset) == 'number') { //WebKit
  var getTop = function() {
   return window.pageYOffset;
  }
 } else if (typeof(document.documentElement.scrollTop) == 'number') {
  var getTop = function() {
   return Math.max(document.documentElement.scrollTop, document.body.scrollTop);
  }
 } else {
  var getTop = function() {
   return 0;
  }
 }
 if (self.innerHeight) { //WebKit
  var getHeight = function() {
   return self.innerHeight;
  }
 } else if(document.documentElement.clientHeight) {
  var getHeight = function() {
   return document.documentElement.clientHeight;
  }
 } else {
  var getHeight = function() {
   return 500;
  }
 }
 function move() {
  if (initTop > 0) {
   pos = getTop() + initTop;
  } else {
   pos = getTop() + getHeight() + initTop;
  }
  if (pos > bottomLimit)
   pos = bottomLimit;
  if (pos < topLimit)
   pos = topLimit;
  interval = top - pos;
  top = top - interval / 3;
  obj.style.top = top + 'px';
  window.setTimeout(function () {
   move();
  }, 25);
 }
 function addEvent(obj, type, fn) {
  if (obj.addEventListener) {
   obj.addEventListener(type, fn, false);
  } else if (obj.attachEvent) {
   obj['e' + type + fn] = fn;
   obj[type + fn] = function() {
    obj['e' + type + fn](window.event);
   }
   obj.attachEvent('on' + type, obj[type + fn]);
  }
 }
 addEvent(window, 'load', function () {
  move();
 });
}