Chain.implement({
  wait: function(duration){
  return this.chain(function(){
    this.callChain.delay($pick(duration, 500), this);
    }.bind(this));
    }
});

wid=document.documentElement.clientWidth

function annoy() {
  document.getElementById('att').style.top = 300*Math.random()+"px";
  var myFx = new Fx.Tween($('att'),{
    property:'left',
     duration:6000,
     transition: 'quad:in:out',
     link:'chain',
     onChainComplete: function() {setTimeout("annoy()",15000+15000*Math.random());}
  });
  myFx.start(0-wid/2,wid/2).start(wid+wid/2);
  
}
setTimeout("annoy()",5000+5000*Math.random());