(function ($) { $.fn.lavaLamp = function (o) { o = $.extend({ fx: "linear", speed: 500, click: function () { } }, o || {}); return this.each(function () { var me = $(this), noop = function () { }, $back = $('<li class="back"><div class="left"></div></li>').appendTo(me), $li = $("li", this), curr = $("li.selected", this)[0] || $($li[0]).addClass("selected")[0]; $li.not(".back").hover(function () { move(this); }, noop); $(this).hover(noop, function () { move(curr); }); $li.click(function (e) { setCurr(this); return o.click.apply(this, [e, this]); }); setCurr(curr); function setCurr(el) { $back.css({ "left": el.offsetLeft + "px", "width": el.offsetWidth + "px" }); curr = el; }; function move(el) { $back.each(function () { $(this).dequeue(); }).animate({ width: el.offsetWidth, left: el.offsetLeft }, o.speed, o.fx); }; }); }; })(jQuery);