PHPLiveSupport - http://www.phplivesupport.com
ClickChatSold - http://www.clickchatsold.com
PHPLiveHelper - http://phplivehelper.com
Bravenet (HumanClick) - http://www.bravenet.com/samples/humanclick.php
LivePerson - http://www.liveperson.com
Chattist - http://www.chattist.com
LiveHelper - http://www.livehelper.com
Live2Support - http://www.live2support.com
Click121 - http://www.click121.com
CS Live Help - http://www.craftysyntax.com/livehelp/
PHPOnline - http://www.dayanahost.com/phponline.cfm
Get1On1 - http://www.get1on1.com