Complete version of PBX in software runs on Linux and other Unix-based machines. Offers voice in three protocols and can interact with many standard telephone systems.

Full-featured VoIP, video and instant messaging software delivers a host of communications options.

Designed so gamers could share voice communications during space battles, RogerWilco offers peer-to-peer voice telephony.

Presents free peer-to-peer telephone communications as well as low-cost integration to land lines.

Allows users to share voice and video communications.