What I've built here is a temperature control system for my PC using an Arduino Uno board and LCD with a few sensors mounted in the case, temperature is averaged.  I have also added Adafruit's EZ-LINK Bluetooth module, which I am controlling using a modified version of ArduDroid for Android developed by http://www.techbitar.com/ardudroid-simple-bluetooth-control-for-arduino-and-android.html.  The app allows me to use analogwrite() to fade strips of LED's placed around my room, as well as digitalwrite() to get temperature data on my phone.  This is very useful as I use my PC for heavy renderings and can monitor it while out of the room, although the range is limited.  The mount above will be added as soon as I finish fixing my 3D printer!  Damned linear bearings...