Linphone - Linphone is an internet phone or Voice Over IP phone (VoIP).
YouTube - Our mission is to give everyone a voice and show them the world.
Zoiper - Cross-platform VoIP softphone dialer for SIP and IAX systems
Facebook Gaming - Watch and stream live games on Facebook
Sipdroid - Free and open-source SIP/VoIP Client
YouNow - YouNow is a free social networking app that allows you to connect with other users via live video broadcast.