/* with great power comes great responsibility, but make sure you have it ;) */
var today = new Date();
var expire = new Date();
expire.setTime(today.getTime() + 3600000*24*90);

$(document).ready(function(){
  $("img.theme_changer").bind("click", function(){
    var b_id = $(this).attr("name");
    $("body").attr("id", b_id);
    document.cookie = "bg_id" + "="+escape(b_id) + ";expires="+expire.toGMTString() + ";path=/";
  });
});