When I had a store that sold Macs, one of my salesmen was a jerk that thought he was a Mac expert. Every night he would leave with 40 or 50 icons on his desktop of things he had open. I couldn't convince him to close up everything and shut off the computer. I finally took a screen shot of his comp with all the icons and made it the background. Then closed up all the icons except for the computer itself and dragged that one off the screen. When he came in the next morning, nothing he clicked on worked. He never did figure out what was going on. Finally turned the comp in for service.