What\'s the best JS or JQuery-specific approach to monitor a cookie through-out the page life on the browser and trigger an event, when the cookie is\' changed?
There is a jQuery plugin for cookies.
http://plugins.jquery.com/project/Cookie
It is not difficult to access the cookies in a html document, they live in document.cookie.
$.cookie('cookieName':'cookieValue');
$.cookie('cookieName');
$.cookie('cookieName', null);
Additionally there are options arguments for add a cookie, e.g. expiry.
However in reply to your question, I don't actually think you can apply a event listener on to cookies unfortunately.