Jquery Center Function

gistfile1.txt

jQuery.fn.center = function() {
    _TOP = (($(window).height() - this.outerHeight()) / 2) + $(window).scrollTop();
    _TOP = (_TOP <= 0) ? 0 : _TOP;
    _LEFT= (($(window).width() - this.outerWidth()) / 2) + $(window).scrollLeft();
    _LEFT = (_LEFT <= 0) ? 0 : _LEFT;
    this.css({
        top:_TOP + "px",
        left:_LEFT + "px"
    });
    return this;
}