Project Gizmo?
Hey look, it’s Michael Robertson’s attempt at cloning Skype: Project Gizmo. Since it basically is using the existing SIPphone infrastructure to pull it off, it’s definitely SIP, it’s definitely got connectivity with other SIP networks, and they’ve got inbound and outbound PSTN connectivity.
Of course, if they want to go head-to-head with Skype, they’re going to have to get clients out there for Linux, Pocket PC, and Symbian. God, I wish I could find a free SIP client for my Nokia 9500…