An Open Source Prank Application!
BlackScreen is a cross platform application that makes your monitor look black, no desktop, icons, or even your cursor. It's a great way to prank your family, and friends. Go ahead, and give it a try, just don't get the crap beat out of you :)
Desktop looks the same, but you actually have a program in fullscreen, at 1% opacity, and it's stopping you from opening programs, folders, images, etc: Great way to prank your friends :) and easy to close by pressing ALT+F4