Hmm...this one was a couple of years back at my first job. This dude was just out of college and considered himself to be too smart to be worldly possible. Well, it was then that couple of us as a group decided to let him know that he is just another Joe Doe in the software industry.

I got an opportunity to find his computer unlocked once. So, I went to his desktop and pressed the "Print Screen" key on the keyboard. Then I opened Microsoft Paint, clicked on edit and clicked paste. I saved this picture under My documents folder. Then right clicked on the empty desktop to go to the "Properties" window and then clicked on "Backgound". Clicked on the "Browse" button to find the snapshot of the desktop that I had saved and clicked on "Ok". Then I selected all the icons on the desktop and deleted them from the desktop. When this dude came back, and tried to click on the icons, he found that none of his desktop icons was working. He freaked out and started asking all the people around him if there has been any virus attack. We all played dumb. It was worth looking at his red face that time....finally he freaked out and called the admin seeking help for the virus attack. The admin came down and informed him that someone has purposefully made an ass out of him. We all had a great laugh and it's still a secret to him that who made his life miserable ;)

This incident may not have transformed him overnight, but atleast he realised what the whole team thinks about him!!