On the most recent episode of Boing Boing TV, MAKE Editor-in-Chief Mark Frauenfelder shows off the Boing Box he made. A Boing Box is a simple analog sound generator used for old-school radio and TV sound effects. There will be more about how he made his in the forthcoming issue of MAKE (Volume 12).

Boing Boing TV, Episode 10/10/07 – Link
Things that go “booooiiinnnggg!” in the night (Basic online instructions) – Link