I saw someone on this forum was working on building a TVBGone/sonic screwdriver prop. ( http://arduino.cc/forum/index.php/topic,1604.0.html ) Unfortunately, that topic is now closed.
I was in the beginning stages of doing the same thing. ( sonic screwdriver | MakerBlock - Part 3 ) ( Sonic Screwdriver GoodFET enclosure by MakerBlock - Thingiverse )
Any interest in helping?
Regards,
MakerBlock