VoIP SIP and SKINNY quality analyzer and packet / audio recording tool
Open source Fax server software for inbound / outbound internet Faxing
Web based system for Computer Assisted Telephone Interviewing (CATI)
The most affordable CRM system according to Capterra
Unified Communications Server
Enterprise telephony recording and retrieval system
Multi user address book application accessable through the web.
Cress is a comprehensive toolset for graphical service/workflow design
JAvascript Voicexml InterpretER
A P2P Messenger which uses JXTA. It provides secure RSA/AES end-to-end
A suite of open-source tools and frameworks for creating SIP apps