12Voip is free Portable Voice Over IP software (Internet Phone). Like many other VOIP products, it enables a computer user with internet access to have superb high quality voice conversations with friends and relatives from all over the world.
Here is a Codyssey Skype Portable launcher that can be used to convert an existing installation of Skype VOIP software on your PC to a portable Skype version that can be stored and run from a USB drive.
TeamTalk is Portable VoIP software that enables a user to easily communicate with their friends, colleagues or clients via Voice over IP communication. Much like TeamSpeak, with TeamTalk any number of people can participate in a conference type conversation, only limited by the bandwidth available to each user.
MicroSIP is Free VO IP "Voice Over IP" software. It can be used to send and receive phone calls or video calls (Point to Point) for Free by IP address.
Loudtalks Lite is a Free Portable Tool that supports Push to Talk (PTT) Voice Over IP (VOIP) communication. It functions similar to popular software like Skype.
PicoPhone is a Free VOIP Internet Phone application with chat. The author created PicoPhone because most Internet phones use overly complex protocols that can cause problems when used with NAPT routers.
Phoner Lite is a Portable VOIP (Voice Over IP) or Internet Phone that can be used to "make phone calls using your computer" enabling you to establish Voice over IP communication with your friends, colleagues, clients and more. Phoner Lite is Freeware and shares the same basic code as Phoner, however utilizes a different GUI.
Phoner is Free electronic portable VoIP Internet Phone software that enables a user to make and receive VoIP calls through SIP. Perform Voice over IP communication with your friends, colleagues, clients etc.