Long ago, I worked at a television station as the IT manager.
We upgraded the weather system from a clunky hard-to-maintain box to a set of easily-configurable systems that ran Unix.
I knew enough to navigate the filesystems and do minor updates.
So, when I found the sprites directory, I realized I could play a few pranks.
With a few copy commands, I replaced the Santa sprite with a flaming meteor.
So on Christmas Eve, instead of Santa flying over the map, there would be a flaming meteor.
But the savvy weatherguy changed it back before they went on air.