Clari - Clari is a predictive analytics platform for sales people.
Asterisk - An open source telephony switching and private branch exchange service for Linux.
InsightSquared - #1 for Salesforce.com Pipeline forecasting, profitability analysis, activity tracking: all the small business intelligence you need. Works using CRM data and automatic syncing.
FreeSWITCH - FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications.
Forecastio AI - Gain actionable sales pipeline insights, build accurate sales forecasts, automate sales planning, and forget about complex, time-consuming spreadsheets.
FusionPBX - FusionPBX is an open source FreeSWITCH GUI.