I worked for Xerox Office Systems Division, fresh out of college, in the Palo Alto / Stanford Research Park, and later, across town at the Bayview facility near the golf course. During my time there, people played hack jokes on each other quite a lot.
Xerox OSD employees each had a Xerox Star 8010 workstation, known internally as a Dandelion(D-) machine. The 8010 was a $10,000 workstation (768KB of RAM and an 8-inch 40 or 80 MB disk drive) that was performance-competitive with machines costing $20,000 - $30,000. It ran a 16-bit stack instruction set using byte-code operations, implemented on microcoded AMD 2901 bit-sliced processors. With four of these 4-bit ALU slices, you could daisy-chain them together and build a decent machine. When I arrived they only ran MESA, Interlisp, and Smalltalk (each environment had a different set of microcode), but when we implemented a C compiler in 1985, I ported the Dhrystone benchmark and discovered that these bit-sliced 16-bit processors produced the same performance as a VAX 11/750 that retailed for $25,000.
One day a college new-hire was talking with one of our senior microcoders, a guy who was 29 years old. The new college-hire wasn't really aware that the 29-year old wrote the microcode for the MESA environment. At one point he said, ''I just can't see why we need microcoders, now that the machine is running, those guys just sit on their asses and don't do much!'' The microcoder-guy bristled but didn't respond to this comment.
The next morning when the new-hire arrived, he sat at his desk and reached for the mouse. When he moved the mouse up, it went down on the screen. When he moved it left, it went right, and so forth. The microcoder had taught him a lesson about his importance!
When you came to work at Xerox, on the first day a tech would visit and bring you a new machine. The tech would plug in the machine, make sure you had the latest microcode, and then download the latest Pilot OS and make sure everything was working. There was no logon to the development environment, but there was login to the network services. Then, the tech would depart. During install the tech would remove the case's side panel, and for certain "very green" new hires, he would install the guts of a talking clock, wired to the workstation power supply, in the extra space in the case. Thereafter, for the next few weeks, on the hour, the new-hire's machine would say in a quiet feminine voice, "It's 10 O'clock" and then fall silent, "It's 11 o'clock" and then fall silent, etc. It was just short enough and quiet enough to drive somebody crazy. Finally after enough of this, the new-hire's office mate would admit the hack, and later that day the tech would return to remove the clock.
One day a new-hire said to a more senior person, "You couldn't play a hack of me if you wanted!" which was the wrong thing to say! The next morning, when the new-hire arrived, they reached for the mouse (but the laser sensor had been taped over), and nothing could move the pointer on the screen. Just as they were getting frustrated and saying to their officemate, "What's wrong with my mouse?", the phone rang. They picked up the phone and it continued to ring! (the 2 cradle buttons that sensed handset pick-up had been taped over, and were still down!) As they continued trying to get the mouse to work, and saying "Hello? Hello?" and the phone continued to ring, in a moment of great confusion, they said "Hello? Hello?" to the mouse. A mouse is not a walkie talkie!