We've done all kinds of crap like that at work- antisieze under the handles of the techs' toolboxes, taped down the buttons on the phone reciever, unplug service writer's phones, unplug the writer's computer (the whole computer) when they have an RO tied up and leave for lunch.
I used a roll of stretch wrap on a guys car once, wrapped the whole thing, after covering his windows in shoe polish.
