Mistbox - Save 30% on your air conditioning bill
Home-Assistant.io - Home Assistant is an open-source home automation platform running on Python 3.
Zen Thermostat - Control the temperature of your home anytime, from anywhere
ioBroker - flexible and modular application for the IoT and Smarthome
ecobee - The smarter wi-fi thermostat
openHAB - "empowering the smart home" - vendor and technology agnostic open source home automation