Wren - Offset your carbon footprint by saving rainforests
Home-Assistant.io - Home Assistant is an open-source home automation platform running on Python 3.
YAYZY - Track the carbon footprint of each purchase in real-time
ioBroker - flexible and modular application for the IoT and Smarthome
Capture - A great free screen capture utility that allows you to capture either a window or the desktop and save it to either a file or the clipboard.
openHAB - "empowering the smart home" - vendor and technology agnostic open source home automation