1)   ScreenStream 1.05
ScreenStream lets others 'watch' your screen while you work. It can be used as the modern equivalent of the overhead projector.
conferencing, desktop sharing, screen sharing, application sharing, online meetings, web demos, remote support, online training, web collaboration, screen presentation,

 2)   DKMessenger v4.5.2
DKMessenger is a free P2P messenger with video, Voice Over IP, text chat, and file transfer capabilities. If you have a microphone and a camera hooked up to your PC, DKMessenger works as a free videophone.
Video, VoIP, application sharing, peer-to-peer, chat, messaging, speech synthesis,

 3)   OfficeSIP Server 1.0
Enable your employees call each other for absolutely free no matter where they are in the world. Use regular telephones, including wireless handsets or headsets, and don’t pay a penny for long-distance calls!
SIP, server, IM, VoIP, instant messaging, voice conversation, whiteboard, application sharing,