count urls with javascript

Hi,

Not sure if this could be done...but is it possible to make a script that would tell you the most amount of people that were online at your forum by counting the profile urls in the source code, then displaying the amount and time and date, then it would change if the number increased?

Or could there be another way of doing it?

Thanks

Peter :)

this site does it, but i think you need pearl, php, or something like asp. something server side.