AJAX constant checking for new posts

Hi there,

I was wondering if anybody knows a way to use Ajax/jQuery (or any other js library for that matter) to keep constantly checking if a new post has been submitted via wordpress. I would like to add this feature to my site so when people are casually browsing then a little box may pop down or some form of notification to inform them that a “breaking new” post has been submitted.

Something similar to what twitter, tumblr and gmail use.

It also doesn’t have to be limited new posts, it could just be some way for a webmaster to post messages to users without a refresh. I presume this should be fairly trivial but I don’t have a huge amount of knowledge in jQuery or Ajax yet…

Any suggestions,

Thanks in advance for replying
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