Hey guys I'd like to share my experience with Comm100 Live Chat Software. I have done a research on the Live chat software at first and finally found a live chat service (2 years back) which offers hosted Live chat software absolutely free. It has all the features like others have.
New here and also interested in this one... Seems SKYPE is getting many votes but I don't think it's good enough for a business website...
For me the best live chat software is Gtalk, In past i prefer to use Yahoo but is has a lot of bugs and their voice quality is really bad against Gtalk.
Exactly why I recommend VideoWhisper. It is strong enough for business purposes, can be white labeled and has many, many options.
Free users, who need temporary solution, use Skype. Live2support is not only an application of live chat but it also provides other required facility for your business. You can support your customer, real time chat with website visitors, collect data for business analysis etc.