NightMare



NightMare is a scareware application created by Patrick Evans in 1990 for Amiga computers. When executed, it will run in the background. Every 5 minutes, the screen will switch to a picture of a skull, seen from its right side, with its mouth open, teeth covered in blood and a bullet hole on the back with blood leaking from it. This is accompanied by an echoing shriek and happens for a four-fifth of a second.

Links
NOTE: The following video contains a screamer!
 * youtube.com/watch?v=ubFGj4lQSyM