This is the Pyrosphere shown in the Burning Man 2010. I think it is really cool because I like light and fire that are programmed to the music. The Pyrosphere is thirty-seven feet tall and it has ninety-one flamethrowers. So it is quite big. And the best is that it’s control by a Arduino.
Here is a movie of what it can do:
From the site Nexus Burning Man 2010 Photos, from there you can find another page where they are showing how they did it. So go there and get some inspiration.