"Ekiga is a SIP and H.323 compatible VoIP, IP Telephony, and Video Conferencing application that allows you to make audio and video calls to remote users with SIP or H.323 hardware and software. It supports all modern VoIP features for both SIP and H.323. Ekiga is the first Open Source application to support both H.323 and SIP, as well as audio and video. Ekiga was formerly known as GnomeMeeting. To get started: Download Ekiga for your distribution and get a free SIP-Address at ekiga.net."