function showExp(exp_id){
  loadContent('ajax.php', 'c=1&exp_id='+exp_id, 'extra_content_holder');
  var h=document.getElementById('extra_content_holder');
  var IE = document.all?true:false;
  if (!IE) document.captureEvents(Event.MOUSEMOVE);
  document.onmousemove = getMouseXY;
  var tempX = 0;
  var tempY = 0;
  function getMouseXY(e) {
    if (IE) { // grab the x-y pos.s if browser is IE
      tempX = event.clientX + document.body.scrollLeft;
      tempY = event.clientY + document.body.scrollTop;
    } else {  // grab the x-y pos.s if browser is NS
      tempX = e.pageX;
      tempY = e.pageY;
    }  
    // catch possible negative values in NS4
    if (tempX < 0){tempX = 0}
    if (tempY < 0){tempY = 0}  
    // show the position values in the form named Show
    // in the text fields named MouseX and MouseY
    h.style.top=tempY+20+'px';
    h.style.left=tempX+10+'px';
    return true
  }
  
  h.style.display='';
}

function hideExp(){
  var h=document.getElementById('extra_content_holder');
  h.innerHTML='';
  h.style.display='none';
}