Plugin for Newer Post Notification on the frontend

I am looking for a plugin which has the ability to notify the site visitors if a new post has just been posted while they are surfing the site.

An ideal example will be Twitter Search – you get “11 New Tweets” on the top. To bring clarity on this, you may try Twitter Search or use this link: https://twitter.com/search?q=earthquake&src=typd and wait for few seconds – you will get that notification if new tweets were posted around that time.

My wordpress site also requires such a feature where I am posting continuously but my users will not know that posts are being published while they are on my site.

I tried searching plugin repository and also on StackExchange but couldnt find anything close. I think ajax will have a lot of role to play, but I am not comfortable with it. Can someone suggest a plugin or a workaround to achieve this? Many thanks.