People are usually unhappy whenever they're working, so they're always looking for a way to entertain themselves while in their workplace in order to make work much more tolerable. People always manage to find a couple of things that help make time go quicker.
If you're not creative enough to come up with your own stuff, there is always at least one co-worker who's constantly doing entertaining things either by himself or collectively with other coworkers.
The coworkers in the pictures below took it to the next level and managed to entertain all of their coworkers at once with their stunts.
"We shrunk a co-worker's desk while he was on vacation. (Art Director for scale)"