Best jQuery scrollTo script, forked from http://lions-mark.com/jquery/scrollTo/

jQuery.scrollTo.js

$.fn.scrollTo = function( target, options, callback ){
  if(typeof options == 'function' && arguments.length == 2){ callback = options; options = target; }
  var settings = {
    scrollTarget  : target,
    offsetTop     : options && options.offsetTop || 0,
    duration      : options && options.duration || 500 ,
    easing        : options && options.easing || 'swing'
  };
  return this.each(function(){
    if ( this.isScrollingTo !== true) {
      var scrollPane = $(this);
      var scrollTarget = (typeof settings.scrollTarget == "number") ? settings.scrollTarget : $(settings.scrollTarget);
      var scrollY = (typeof scrollTarget == "number") ? scrollTarget : scrollTarget.offset().top + scrollPane.scrollTop() - settings.offsetTop - scrollPane.offset().top;
      this.isScrollingTo = true;
      scrollPane.animate({scrollTop : scrollY }, parseInt(settings.duration), settings.easing, function(){
        this.isScrollingTo = false;
        if (typeof callback == 'function') { callback.call(this); }
      });
    }
  });
}