So my students were joking around after cleaning time, and one boy comes up to me and says, "My nickname is 'Slow Pikachu,' because I'm like Pikachu but not as fast." What's your nickname?
I replied I didn't have one and he said he'd make me one. He thinks for a second and says, "Ah! Patrash!"
Now if he had arrived at that name because I was always after him about picking up the trash (which I am, since he's the only boy able to make the room dirtier during cleaning time), I would have been impressed, but he didn't know the word "trash."
Later nickname suggestions included "Patri", "Patr" "Pa" and "Patrick." When I explained to him Patrick was my name, and therefore could not be a nickname, there was a brief pause, an epiphany, and then a sudden running away.