Reality Editor - MIT's new app lets you program any object
Home-Assistant.io - Home Assistant is an open-source home automation platform running on Python 3.
My Devices - Drag and drop IoT project builder for Raspberry Pi
ioBroker - flexible and modular application for the IoT and Smarthome
Stringify - Smart Automation Home, Work, Life, IoT
openHAB - "empowering the smart home" - vendor and technology agnostic open source home automation