Home-Assistant.io - Home Assistant is an open-source home automation platform running on Python 3.
Tep - Fitness tracker meets tamagotchi. Don't starve it!
ioBroker - flexible and modular application for the IoT and Smarthome
HB Ring - See and feel the real-time heartbeat of your loved one
openHAB - "empowering the smart home" - vendor and technology agnostic open source home automation
Nimb - Smart ring with a panic button