I was originally planning on using the PiFace Digital 2 to control relays to turn an analog LED strip embedded in the desk on or off. Since then, I came across a library to control addressable LED strips (or NeoPixels) via the Pi’s GPIO. The library doesn’t function with the Pi 2 (yet), but it does with the A+/B+ which I was planning to use for the desk controls anyway.
One concern I was having, is that the addressable LED strips operate at 5V. I wasn’t sure a 3.3V GPIO pin from the Raspberry Pi would be sufficient to control the strip and that I might have to use some logic level conversion. Well, luck was on my side, as it appears that no conversion is required and the strip can be controlled directly from the Pi’s GPIO.
A guide on how to control the LEDs and install the library can be found here: Controlling NeoPixels with the Raspberry Pi A+/B+
I can now proceed by defining custom animations based on triggers such as received emails or hashtags being used on twitter for example.