diff --git a/app/assets/javascripts/announcement_refresh.js b/app/assets/javascripts/announcement_refresh.js
new file mode 100644
--- /dev/null
+++ b/app/assets/javascripts/announcement_refresh.js
@@ -0,0 +1,41 @@
+
+var Announcement = {
+
+    mostRecentId: 0,
+
+    refreshUrl: '/main/announcements',
+
+    setMostRecentId: function(id) {
+	Announcement.mostRecentId = id;
+    },
+
+    updateRecentId: function(id) {
+	if(Announcement.mostRecentId < id)
+	    Announcement.mostRecentId = id;
+    },
+
+    refreshAnnouncement: function() {
+	var url = Announcement.refreshUrl;
+	new Ajax.Request(url, {
+	    method: 'get',
+	    parameters: { recent: Announcement.mostRecentId },
+	    onSuccess: function(transport) {
+		if((transport.status == 200) && 
+		   (transport.responseText.match(/\S/)!=null)) {
+ 		    var announcementBody = $("announcementbox-body");
+		    announcementBody.insert({ top: transport.responseText });
+		    var announcementBoxes = $$(".announcementbox");
+		    if(announcementBoxes.length!=0)
+			announcementBoxes[0].show();
+		    Announcement.registerRefreshEventTimer();
+		}
+	    }
+	});
+    },
+
+    registerRefreshEventTimer: function() {
+	setTimeout(function () {
+	    Announcement.refreshAnnouncement();
+	}, 30000);
+    }
+};