Installing "Hannah Montana Linux" on a co-worker's pc after they left it unlocked and went home for the weekend.

Ahahahaha, I didn't know something like that even existed...

Bugger, too late to edit, but I should probably mention that my employer has an unofficially official "don't leave your PC unlocked" policy, and breaching of said policy leaves you(r pc) free game for anyone to mess with.

@antoni4040 Oh yeah, as soon as I found it I knew for sure it would be going on the next pc that got left unlocked, haha. We weren't too harsh though, ghosted his boot disk and left the image on an external drive before installing it.

The drive containing the image, however, was left inside his pc's case, took him a while to find it, haha.

@runfrodorun oh yeah, I know. But the rule is, you leave it unlocked, you get punished!

Eh, could be worse.
You could have installed Biebian.