How about something like http://extensions.joomla.org/component/option,com_mtree/task,viewlink/link_id,1078/Itemid,35/ But you need Joomla..
xooChat is remotely hosted Live Customer Support script. It's actually not free but it worths to look at to see it has a lot of advantages.
If you are using cpanel with fantastico,Use Crafty Syntax Live Help,You will find it in fantastico scripts.Easy install and setup,Requires small code to be inserted to webpage to intergrate. It will tell you how manny online-tracks keywords-tracks page views etc. Great for live chat help. Need help to install and setup? give me a shout If you dont have fantastico http://www.craftysyntax.com/
I've used craftysyntax and it has a lot of bugs and is crashing very often. I also tried phpOnline - not bad but the admin desktop version does not have alerts when someone is requesting a chat. ChatStat is the bst so far.
We've just installed ProvideSupport although not free as you were looking for. It has a nice standalone operator console for Windows which we really like and consider worth the money. Your situation may vary though... You can set it to pop up/make a sound whenever someone visits the site, etc. If you prefer one can use the web based console also... So far so good... Verlin ------- Juvederm Injectionshttp://www.rxpad.biz
Not free unfortunately, but I use phplive. I have found it to be the fastest and cleanest solution at a reasonable price to own it. Nigel Edit: Actually, this may be good. I have not tried it. http://helpcenterlive.com/dru//node/34
Crafty Syntax Live Help Help Center Live osTicket PerlDesk PHP Support Tickets Support Logic Helpdesk Support Services Manager support services manager is the bset one! here is a demo http://webgamesnetwork.com/livechat/