30th Chaos Communication Congress: http://events.ccc.de/congress/2013More Info on this DIY Pneumatic Tube System: https://events.ccc.de/2013/12/08/seidenstrasse/It needs an empty cut open spray can and a LED lightstrip (with a23 battery and holder) to be complete. You can get spraycans from us at the event - ask at the DJ Booth at Villa Straylight. Other then that you can fit a LED Strip behind the "Windows" in the top and there is everything there to wire it and make it even turn on once you put in the Spraycan.