PiDome.org - PiDome is the Home Automation Platform for the Raspberry Pi containing a server, multiple clients with user friendly interfaces
openHAB - "empowering the smart home" - vendor and technology agnostic open source home automation
MyController.org - MyController.org is an IoT automation controller for home, office or any place.
Home-Assistant.io - Home Assistant is an open-source home automation platform running on Python 3.
ioBroker - flexible and modular application for the IoT and Smarthome
Calaos - Open source home automation