VoipUser.org
Provides SIP account for their registered users.
SIP2SIP
You may use this service to register a SIP account that allows you to communicate using audio and video over the Internet using the SIP protocol. The account is Presence/IM enabled with support for relevant SIP SIMPLE standards for MSRP relay extension, Presence Agent, XCAP and RLS services.
IdeaSIP
Need to stay in touch with friends, family, or colleagues? What if we offered you the ability to communicate with anyone, anywhere, at any time via voice, video, or IM all absolutely free? We’re not talking free the way cell phone companies offer ‘free minutes,’ or the way the big phone companies offer ‘free long distance.’ At IdeaSIP, free means NO monthly charges, NO signup fees, NO hidden fees, NO ads, NO strings. We’re talking about absolutely 100%, honest-to-goodness free. This is the power of IdeaSIP. Think we’re crazy?
Note: 28.10.2010 – we will see hot the service will evolve