I remember downloading what I thought was a no-CD crack for some game from Kazaa.

It was an app that locked my screen, opened a window, and systematically deleted every folder in my main C: drive before crashing. Then the screen went black and a message popped up that said "Thank god it's only a game."

The exe was an ad for some indie Doomclone FPS game where the levels were your computer's file structure and the walls of the rooms would be decorated with the images stored in your folders. I shut down my machine after that. I was shaking for the next hour.

If anyone knows the game, I'd love to learn what it was all about.