Home-Assistant.io - Home Assistant is an open-source home automation platform running on Python 3.
Save Hollywood - Play movies as your screen saver
ioBroker - flexible and modular application for the IoT and Smarthome
Padbury Clock Screensaver - Minimal screensaver for Mac
openHAB - "empowering the smart home" - vendor and technology agnostic open source home automation
HotShots - Hotshots is a screenshot tool with some editing features.