Marvin is built out of waste thermocol (that came with the packing of my monitor). It has a small red breadboard attached as it's heart. The light on the heart glows green if there are more tweets with positive sentiment going around in the (All izz well) and glows red if there are more tweets with negative sentiments going around in the virtual world. (I took about a handful of words like "environment", "plastic", "global warming" etc. as the baseline hashtags to be analyzed for sentiments) More on the implementation of the Arduino controlling the LEDs can be found on my blog.