Arduino Forum User [Donster] posted a project about a Christmas Tree whose lights are lit by the word “Merry Christmas” on twitter:
The basic idea is having the lights on the Christmas Tree turning on everytime someone tweets “Merry Christmas”.
It’s still pretty much a prototype but you get the idea. Sometimes the live stream gets out of synch with the tweet overlays, but generally it stays on track.
The actual setup is really all based off a lot of relays running 12V 1W LED’s. I started out with 10W halogens and after a few burnt tree branches I decided to try and find an LED which gave off as little heat as possible! It also meant a 20Amp powerpack could run all 30 lights.
This is the setup of the all project: