Ninja Blocks are simple but powerful open source hardware backed by an amazing web service called Ninja Cloud that allows your Ninja Block to talk to your favorite web apps.
Each Ninja Block comes with an RGB LED and built-in temperature sensor and accelerometer. Four expansion ports and a regular USB port allow you to add further inputs and outputs.
Ninja Cloud allows you to control your Ninja Blocks without writing a single line of code.
This is a nifty idea and very well thought-out, but it gets even better, because Ninja Blocks are open-source hardware. They have pushed the Eagle files to github, so you can check them out (or make your own).