var xPos = 350;
  var yPos = 60;
  var step = 2;
  var delay = 100;
  var width = 0;
  var height = 0;
  var offset_x = 0;
  var offset_y = 0;
  var xon = 20;
  var yon = 20;
  var name = navigator.appName;
  if (name == "Microsoft Internet Explorer") 
   {
   //xPos = document.body.clientWidth;
   float2.style.left = xPos;
   //yPos = document.body.clientHeight;
   float2.style.top = yPos;
  }
  else 
  {
   //xPos = window.innerWidth;
   document.float2.pageX = xPos;
   //yPos = window.innerHeight;
   document.float2.pageY = yPos;
   document.float2.visibility = "hidden";
   }
function changePos() 
{
  // move
  if (xon ==0) 
   {
    xPos = xPos - step;
   }
  else 
   {
    xPos = xPos + step;
   }
  if (yon == 0) 
   {
    yPos = yPos - step;
   }
  else 
   {
    yPos = yPos + step;
   }
  // get W/H
  if (name == "Microsoft Internet Explorer") 
   {
    width = document.body.clientWidth;
    offset_x = float2.offsetWidth;
    height = document.body.clientHeight;
    offset_y = float2.offsetHeight;
   }
  else 
   {
    width = window.innerWidth;
    offset_x = document.float2.clip.width;
    height = window.innerHeight;
    offset_y = document.float2.clip.height;
   }  
  // turn around
  if (xPos < 0) 
   {
    xon = 1;
    xPos = 0;
   }
  if (xPos >= (width - offset_x)) 
   {
    xon = 0;
    xPos = (width - offset_x);
   }
  if (yPos < 60) 
   {
    yon = 1;
    yPos = 60;
   }
  if (yPos >= (height - offset_y)) 
   {
    yon = 0;
    yPos = (height - offset_y);
   }
  // scroll
  if (name == "Microsoft Internet Explorer") 
   {
    float2.style.left = xPos + document.body.scrollLeft;
    float2.style.top = yPos + document.body.scrollTop;
   }
  else 
   {
    document.float2.pageX = xPos + window.pageXOffset;
    document.float2.pageY = yPos + window.pageYOffset;
   }
}

function start()
{
  if (name != "Microsoft Internet Explorer") 
   {
    document.float2.visibility = "visible";
   }
  loopfunc();
}

function loopfunc()
{
  changePos();
  setTimeout('loopfunc()',delay);
}