The Express Talk softphone works like a telephone to let you make calls through your computer and you can call anyone via the internet who has installed it (or any other SIP softphone)
Voix Manager was developed in c++ and is multi-platform, comes complete with an IAX2 telephone, and an interface for managing internal and external phone lines (VoIP, POTS or ISDN), which is self-configuring with the Asterisk Manager.
designed to work with Voice over Internet (VoIP) phone systems. ScreenPop combines two of the most sought after features - screen pop and call rejection
designed to work with Voice over Internet (VoIP) phone systems. SoloRecord combines three of the most sought after features - call recording, call rejection, and screen pop