スライドサイドバー(フッターの上で止まるやつ)
スライドさせたはいいがフッターと被ったので。
参照:http://select-aster.com/web/auto-tracking-sidebar/

----------------html部分-----------------------
<div  id="aside2">
スライドさせたい要素
</div>
-----------------------------------------------

----------------script&CSS部分-------------------
<script src="jquery.min.js"></script>
<script type="text/javascript">
<!--
$(function(){
    var target = $('#aside2');
    var footer = $('#footer')
    var targetHeight = target.outerHeight(true);
    var targetTop = target.offset().top;
    $(window).scroll(function(){
        var scrollTop = $(this).scrollTop();
        if(scrollTop > targetTop){
            var footerTop = footer.offset().top;            
            if(scrollTop + targetHeight > footerTop){
                customTopPosition = footerTop - (scrollTop + targetHeight)
                target.css({position: "fixed", top:  customTopPosition + "px"});
            }else{
                target.css({position: "fixed", top: "10px"});
            }
        }else{
            target.css({position: "static", top: "auto"});
        }
    });
});
-->
</script>
<style>
div#aside2.fixed {
    position:fixed;
    left:0px;
    top:10px;
    z-index: 1;
}
</style>
----------------------------------------------