Skype is a megapopular program with which you can make voice and video calls to all corners of the globe absolutely free. Developers declare complete privacy of communication and personal data, which is achieved by encrypting traffic.
TeamSpeak is a free application for voice communication between users via a local network or the Internet. You can create your own channel with a real-time conference. Perfect for gamers when large group coordination is needed.
Pamela for Skype Basic is a great addition to Skype, which allows the user to record incoming and outgoing calls. Also, the utility contains an answering machine, auto answer in chat and many other features.
The program provides virtual fax machines for the fax service, and allows you to use Microsoft Fax and Fax and Scan applications built into Windows to send and receive T.38 and audio faxes using VoIP (SIP / H.323) services
A universal application that provides an ideal solution for organizing fax and voice mail in a SIP, H.323 or ISDN network. Works with VOIP or ISDN PBX or with your SIP / H.323 / ISDN operator. Up to 100 virtual lines supported
An application through which users can make and record phone calls. The program supports the playback of the melody on hold, there is call forwarding, sending faxes and audio messages, there is a phone book
ooVoo is a free program for video communication over the Internet. Allows you to communicate one on one or with several people at the same time (up to 6 people). The videoconference window is rather unusual - the interlocutors are shown in the 3D dimension
Nimbuzz is a free and easy-to-use all-in-one solution for comfortable communication, allowing you to use the most popular services, such as ICQ, ALM, Yahoo, Windows Live, Google Talk, Jabber and Twitter, to make voice and video