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 :)
This project builds on the jUSB APIs, initially supporting the Picture Transfer Protocol (PTP) over USB on Linux. The software is GPL'd, and includes an extensible core library (for developers), commandline support, and user tools.