Discord Portable is a stand alone version of Discord; One of the Best Free Chat Apps for gamers. Popular amongst online game players, this software can be used for (VoIP) Voice Over IP, and text chatting. You can use it as a file exchange tool, for transferring files as well. Many prefer it over TeamSpeak and Skype as it is easy to setup and work with. The tool also appears to be less resource intensive than the others.
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. The application supports sending to other people who use the software, or to telephones via your favorite non-free SIP provider.
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. However, with it's distinct advantages, some consider Loudtalks a Skype Replacement. Real Time, Face to Face like voice communication. It's Unobtrusive, you can listen when you want. You can receive messages if you are not at your PC and listen to them later on. You can have multiple independent conversations simultaneously. You can also have live group voice conversations with a few to hundreds of people at once. There are versions for Windows Mobile and Windows devices (So you can also run it from your phone).
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.
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. PicoPhone uses a simple UDP-based protocol and works well with NAPT. Connections are accepted on UDP port 11676.
