Check it out!
I'll never have enough time to use all of these...
Before I left the States I worked in an engineering department of a corporation as a software tech. I was the only SW guy in my cube, the other guys were systems engineers.
On April Fools day I sent an email to one of my unsuspecting cubemates with an attached .exe file. The text of the email instructed my cubemate to turn up the volume on his computer and listen for the 'soft noise' in the program.
Well, I was on my way back to my desk from the restroom when I heard "HEY EVERYBODY! I'M LOOKIN PORN OVER HERE!!" Everybody on our floor was standing up looking over the tops of their cubes laughing and of course my cubemate was sitting at his desk with his head burried in his arms.
He refused to open further emails from me that contained attachments of any kind.