I am looking for a SIP Dialer (JavaScript, PHP or Flash) run on client end will connect to web-server possibly running Asterisk (in Centos Linux). The web-dialer needs be just like X-lite for PC but runs on client browser. Asterisk connect to PSTN via ATA. I have seen few companies that provide web-dialer based on JavaScript but they want to connect to their own VOIP service at higher rates.
I would also like list of free SIP providers.