After browsing on Digg for a few minutes I noticed the then #2 digg item on THX which of course lead reviewing the history of THX trailers to hear that classic sound.
The Story of “Deep Note”For more than two decades, THX cinema and DVD trailers have been wowing audiences with state-of-the-art visuals and the famous “Deep Note” sound effect. Before launching the company in 1983, THX executives decided to leverage their wealth of creative talent and resources at Lucasfilm’s Skywalker Ranch to develop a promotional trailer. However, the company was looking for something that would be more than just another corporate logo flashing on the screen.
Oh yeah, for a good laugh, view the Simpson’s THX