The most affordable CRM system according to Capterra
Unified Communications Server
Unified Communications System - PBX System
Enterprise telephony recording and retrieval system
VozBox. Asterisk VoIP PBX.
vTiger Freeswitch PBX Integration
Cyber-wrt pbx is embedded system in DD-Wrt router
Asterisk and Yate (VoIP PBX) Scripts and Libraries
predictive dialing for vTiger using asterisk
CRM system based on vtiger, adapted to Polish companies.