<table>
    <tr>
        <td><span>Один</span></td>
        <td><span>Два</span></td>
        <td><span>Три</span></td>
        <td><span>Четыре</span></td>
    </tr>
    <tr>
        <td colspan="2"><span>Одиннадцать</span></td>
        <td colspan="2"><span>Двенадцать</span></td>
    </tr>
</table>
table{
    border-collapse:collapse;
    margin:20px;
    border: none;
    }
    td{
        border:1px solid #000;
        }
        td span{
            display: block;
            position: relative;
            margin: -1px;
            padding: 3px 5px;
            border: 1px solid #000;
            }
        td:hover span,  td.hover span {
            z-index: 2;
            border-color:#999;
             }
 
 
/* IE 6 */
* html td {
    behavior: expression(
        function(t, hoverClass){
            t.runtimeStyle.behavior = 'none';
            hoverClass = hoverClass || t.className ? t.className.replace(/([^\s]+)/g,'$1_hover') : 'hover';
            t.attachEvent('onmouseover',function() {
                t.className += (' ' + hoverClass);
            });
            t.attachEvent('onmouseout',function() {
                t.className = t.className.replace(new RegExp(' ' + hoverClass,'g'), '');
            });
        }(this)
    );
    }
 
/* IE 7 */
*+html td {
    behavior: expression(
        function(t, hoverClass){
            t.runtimeStyle.behavior = 'none';
            hoverClass = hoverClass || t.className ? t.className.replace(/([^\s]+)/g,'$1_hover') : 'hover';
            t.attachEvent('onmouseover',function() {
                t.className += (' ' + hoverClass);
            });
            t.attachEvent('onmouseout',function() {
                t.className = t.className.replace(new RegExp(' ' + hoverClass,'g'), '');
            });
        }(this)
    );
    }

var start = new Date().getTime();
for (i = 0; i < 50000; ++i) {
// do something
}
var end = new Date().getTime();
var time = end - start;
alert('Execution time: ' + time);

(function(){
 
    var special = jQuery.event.special,
        uid1 = 'D' + (+new Date()),
        uid2 = 'D' + (+new Date() + 1);
 
    special.scrollstart = {
        setup: function() {
 
            var timer,
                handler =  function(evt) {
 
                    var _self = this,
                        _args = arguments;
 
                    if (timer) {
                        clearTimeout(timer);
                    } else {
                        evt.type = 'scrollstart';
                        jQuery.event.handle.apply(_self, _args);
                    }
 
                    timer = setTimeout( function(){
                        timer = null;
                    }, special.scrollstop.latency);
 
                };
 
            jQuery(this).bind('scroll', handler).data(uid1, handler);
 
        },
        teardown: function(){
            jQuery(this).unbind( 'scroll', jQuery(this).data(uid1) );
        }
    };
 
    special.scrollstop = {
        latency: 300,
        setup: function() {
 
            var timer,
                    handler = function(evt) {
 
                    var _self = this,
                        _args = arguments;
 
                    if (timer) {
                        clearTimeout(timer);
                    }
 
                    timer = setTimeout( function(){
 
                        timer = null;
                        evt.type = 'scrollstop';
                        jQuery.event.handle.apply(_self, _args);
 
                    }, special.scrollstop.latency);
 
                };
 
            jQuery(this).bind('scroll', handler).data(uid2, handler);
 
        },
        teardown: function() {
            jQuery(this).unbind( 'scroll', jQuery(this).data(uid2) );
        }
    };
 
})();