slide.js

(function($) {

    $.fn.slide = function strength(options) {
        var defaults = {
            'direction': 'left', // can also be 'right'
            'duration': 500,
            'callback': function() {}
        };

        if (options === 'left' || options === 'right') {
            options = {'direction': options};
        }

        options = $.extend(defaults, options);

        var $this = this,
            frame = this.parent(),
            width = frame.width(),
            next = (options.direction == 'left' ? this.next() : this.prev()),
            next_start = (options.direction == 'left' ? width : width * -1);
            this_end = (options.direction == 'left' ? width * -1 : width);

        if (!next.length) {
            return this;
        }

        frame.css({
            'overflow': 'hidden',
            'width': width,
            'display': 'block',
            'position': 'relative'
        });

        this.css({
            'position': 'absolute',
            'top': 0,
            'left': 0
        });

        next.css({
            'position': 'absolute',
            'top': 0,
            'left': next_start
        }).show();

        frame.height(Math.max(this.outerHeight(true), next.outerHeight(true)));

        this.stop().animate({'left': this_end}, options.duration, function() {
            $this.hide();
            frame.css({'overflow': 'visible'});
            options.callback();
        });

        next.stop().show().animate({'left': 0}, options.duration, function() {
            next.css({'position': 'relative'});
            frame.animate({'height': next.outerHeight(true)}, function() {
                frame.css({'height': 'auto'});
            });
        });

        if (frame.offset().top < $(window).scrollTop()) {
            $(window).scrollTo(frame, options.duration);
        }

        return this;
    };

})(jQuery);