Quick/Easy way to get $totalonline users (current active users number)

[nighteyes]

Does anyone know if there's a quick, clean and easy way to get the $totalonline active users number online (i.e. 50) without having to run a whole lot of MySQL and PHP crunching code?

I want to make this number available to vBAdvanced via the Plugin system. Something like this would be ideal:

$totalonline = $vbulletin->userstats['totalonline'];

I already use the following successfully:

$numbermembers = vb_number_format($vbulletin->userstats['numbermembers']);
$newusername = $vbulletin->userstats['newusername'];
$newuserid = $vbulletin->userstats['newuserid'];

Any ideas?