Кнопка наверх

HTML

<div id="content">Content</div>
<div id="footer">Footer</div>

CSS

#footer {
      height:170px;
      background-color: red;
}
#toTop {
      background-color: #0A3C5A;
      border: 1px solid #D11A10;
      color: #FFFFFF;
      cursor: pointer;
      font-size: 16px;
      padding: 2px 10px;
      position: fixed;
      right: 30px;
      display:none;
}
#content {
      height: 1000px;
}

JavaScript

jQuery(function(f){  
        var el = {
          div: {},
          create: function () {
            this.div = f('<div>', {
              id: 'toTop',
              text: '↑ наверх',
              click: function () {
                f('body, html').animate({
                  scrollTop: 0
                }, 800);
              }
            }).appendTo('body');
          },
          bottom: function (a) {
            var b = f('#footer').offset().top,
              c = f(window).height();
            this.div[ 'fade' + (a ? 'In':'Out')]();
            this.div.css({ bottom: b < a + c - 80 ? a + c - b : 80});  
          }
        };
        el.create();
        f(window).bind('scroll resize', function () {
          el.bottom(f(this).scrollTop());
        });
});