Grabbing constantly updating information from a website?

[sphinx]

Is There a script which can be used that will grab constantly updated information from a certain website, and output it onto your own website? By constantly, I mean like:

 

23 Hours, 13 Minutes and 3 seconds ago.

 

Surely this can be done some how?

 

Thanks

 

Could I use:

 

$page_contents = file_get_contents("http://www.example.com");

if i wanted to look for <td>time:</td>

$matches = array();
preg_match('CODE TO LOOK FOR HERE?', $page_contents, $matches);
echo $matches[0];