Guy left his computer unlocked. Boss came over looking for him, sat down at his computer and opened lots of porn and left saying 'that will teach him'.

A bit late but I just remembered this story.. at my college the people in the IT department always watch for when another professor or student leaves their computer unlocked and then change their wallpaper to something funny (e.g. my little pony). One time the instructor from the class before mine left their machine logged in and my professor asked the class "what should we do?"

I suggested he modify the chrome shortcut on the desktop and change the path to 'C:\windows\system32\cmd.exe /c shutdown /r /t 0' then pin it to the taskbar. And he did it.

I wasn't in that class but I heard that she clicked it 3 times before she figured out what was going on. She never fixed it the whole rest of the quarter (simply launching chrome from the start menu) and would occasionally forget and click the taskbar icon and go through the whole thing again.

As fate would have it I got 2 classes with that instructor the next quarter. We're friends so it's all good but I still get flack about it and I don't dare leave my computer unlocked xD

Under the guise of being security conscious, our section had a informal "doughnut charter" whereby if you leave your computer unlocked and someone managed to send an email to the section (cc'ing you) shouting everyone doughnuts then you must comply with the "promise". I was referred to at the time as the "god of email" and everyone knew not to do it to me or I would retaliate. This is because it happened once before. In that case, I set up a secure hidden rule in the person's email so that if they received a doughnut email they would automatically send a doughnut email from them... this also meant it was possible to trigger it at any time. They quickly begged for it to be removed. From then on, no dared touch my unlocked computer. When we got a new boss he was informed of the charter and was repeatedly warned not to 'doughnut' me but one day he ignored the warnings. In his case I set up a rule so that if he sent any email, he also sent out a doughnut email as well. Over the next four days he sent sooo many doughnut emails... He went from happy, to frustrated, to angry and then simply desperate. No one dared tell him I was my doing... He eventually came out of his office and begged for it to stop... Seeing his desperation, I stopped it. He was very appreciative but never put two-and-two together (that his actions caused it). He didn't find out till three months later that I was the one who did it to him. That was the second and last time I was ever doughnut'd.