We did something similar, but it was years before xauth and xhost. It also wasn't anything malicious, just a prank, when you run xeyes on someone else's termin

We did something similar, but it was years before xauth and xhost. It also wasn't anything malicious, just a prank, when you run xeyes on someone else's terminal. They would laugh a little and then continue with their lifes. Nothing serious, requiring sysadmining.