gistfile1.js

// assuming jquery and the cookie plugin are already included.

$("html").addClass("js");

$(document).ready(function() {
	if ($.cookie('exp_alert_banner_newsletter')!='hide') {
		$("p.alert").slideDown("slow");
	
		$("p.alert span.hidealert a").click(function() {
			$("p.alert").slideUp("slow");
			var date = new Date();
			date.setTime(date.getTime() + (3 * 24 * 60 * 60 * 1000));
			$.cookie('exp_alert_banner_newsletter', 'hide', { path: '/', expires: date });
			return false;
		});
	}
});