var drag_=false
var D=new Function('obj','return document.getElementById(obj);')
var oevent=new Function('e','if (!e) e = window.event;return e')
function Move_obj(obj){
var x,y;
D(obj).onmousedown=function(e){
drag_=true;
with(this){
style.position="absolute";
var temp1=offsetLeft;
var temp2=offsetTop;
x=oevent(e).clientX;
y=oevent(e).clientY;
document.onmousemove=function(e){
if(!drag_)return false;
with(this){
style.left=temp1+oevent(e).clientX-x+"px";
style.top=temp2+oevent(e).clientY-y+"px";
}
}
}
document.onmouseup=new Function("drag_=false");
}
}
<div align="center" id="mess" onmouseover="Move_obj('mess')"></div>