[Asterisk-Users] Simple question about SIP community

[Marcello Lupo]

Hi to all,
we have a community of people on an * box that use SIP softphones to talk each 
other. Can you suggest me the quickest and simple way to let someone know who 
is online without have to call one by one the persons to look if they are 
present or not?? Something the user list in Microsoft Messenger.
I was thinking on some sort of web page that can check the registration of the 
sip clients on the asterisk but want to know if already exist to avoid to 
reinvent the wheel.
thanks,
Bye,
MArcello