The Personal Orchestra is an installation which allows everyone to slip into the role of the conductor of the famous Vienna Philharmonic.
The orchestra is projected onto a screen and you take place in front of it. Using an electronic baton you can then control speed and volume of the orchestra. The faster you swing the baton, the faster will the Vienna Philharmonic play. The wider your gestures are, the louder the orchestra will play. You can even emphasize single groups of the orchestra by conducting in their direction.
The technological highlights of this installation are the automatic gesture recognicion and the automatic speed-change of the music (or any audio signal, as far as the technology is concerned) without changing the pitch of it.
There are also a few videos with tv coverage of the installation and technology on the website, but these are mostly in German.