Reigel's demo page

HTML

<iframe id="tail"></iframe>
<br>
<br>
<a id="safe" href="#"> This is a test link!
    <br>
    iframe should not pass over the link area
    <br>
    to avoid the iframe interpose the link! 
</a>

CSS

#tail {
    position: absolute;
    float: left;
    text-align:center; 
    width:40px; 
    height:20px;
    background-color:#CCCCCC;
    border:0;
}


body { text-align:center; }

JavaScript

$(document).bind('mousemove', function(e){
    $('#tail').css({
       left:  e.pageX - 20,
       top:   e.pageY -18
    });
});



$('a').mouseover(function(e) {
    $('#tail').css('display', 'none');
}); 

$('a').mouseout(function(e) {
    $('#tail').css('display', 'inline');
}); 
 

/*
$('a').mouseover(function() {
$(document).unbind('mousemove');
}); 
*/