[kh99]

How does that code work? I guess the number of players online is supposed to appear in place of [..], but I've never seen that before.

Anyway, in a plugin you'd do something like:

$players_online = file_get_contents("http://site.net/site/onlineplayers.php");
vB_Template::preRegister('template', array('players_online' => $players_online));

then in your template you'd use something like:

there are {vb:var players_online} online

You'd have to change 'template' to the actual template you're putting that in, and the plugin "hook location" would depend on which template you're using (although you could use parse_templates to start with).