The most affordable CRM system according to Capterra
Unified Communications Server
Unified Communications System - PBX System
Asterisk based VoIP pbx appliance
A Better PBX For Your Business
Enterprise telephony recording and retrieval system
ERP, IP PBX, Accounting, CRM, Time tracking, and etc.
VozBox. Asterisk VoIP PBX.
Respins of various open source PBX projects