Countdown

Countdown is a screamer video uploaded to YouTube on April 27, 2009 by Steven Anderson.

The video is a timer, counting down from 60. It's fully silent until it counts down to 30 seconds, at which point the theme song from the American game show Jeopardy begins to play, and the numbers turn yellow. When the timer runs out, the screen begins flashing and a buzzing sound will play for 2 seconds; a picture of Regan MacNeil from The Exorcist will appear right after, with a generic, normal female scream. The video is designed to be a prank, aimed at people intending to use this as a countdown for any purpose. The video has accumulated over 300,000 views since its upload.

Link
NOTE : The following video contains a screamer!
 * youtube.com/watch?v=9-N2N9QquSM