The Yakko project is a home automation system. It defines a new protocol implemented as firmware running in AVR atmega microprocessors. The goal is to build a method to make logical connections between hardware devices such as lamps, switchers and so on.
The Wolfram Machine project is an effort to create a set of documentation and useful modules (both hardware and software) for a computing architecture based on the mathematical theories presented in Steven Wolfram's book _A_New_Kind_of_Science_.
Lightget is an open hardware and open software project to build computer controlled systems with LEDs and/or other light sources. The ultimate goal is to provide illumination and visual entertainment in a convenient, low-cost solution.