Our manager commandeered the company van, our vehicle for picking up supplies and parts, for his own personal use. In addition, he had the company paying for his apartment while using the van as his taxi. Things got mysteriously smelly in that van as he drove it back and forth. A generous amount of fish emulsion oil, the liquid fertilizer you get from the nursery, was squirted inside the door panels, under the driver's seat, and graciously allowed to ferment in the summer heat.
In the early days of LANs, there was a Macintosh program called "BSoD" for "blue screen of death"
One could use it to send a ping to a windoze computer which would promptly crash the receiving PC.
Once you knew the IP address of the victims PC, always a sales guy.
In the early days of personal computers, a programme was available whic was triggered by a random sequence of letters. When triggered, it put on the screen something like: "Do you really want to format Drive C: Y/N". It didn't matter what you pressed, the result was always "Formatting Drive C:" and the hard disk light would come on indefinitely. It didn't format anything but the alarm and consternation was something to behold!
Nice ones. Your RF one reminds me of my first job - installing 2-way radios in vehicles in the Police radio workshops in Harare in Zimbabwe. (Come to think of it it was Salisbury in Rhodesia in those days...) Anyway there was a rather cute policewoman who was always in and out of the yard. So whenever she drove in or out, we'd put a dummy load on our radio, ensuring it could be picked up by her but no-one else outside about 100 yards range, and talk to her - a mix of "Welcome back, beautiful!", "Bye, come back soon" and other flirty comments. She eventually found us out, but took it very well. I even went out with her a couple of times after that...thinks...wonder where she is now....
I once worked with a business development manager who liked to listen to a hard rock radio station in his office on the other side of the wall from the lab. We had an RF generator with an FM modulation feature. I hooked up a small loop "antenna" to the generator output, then hooked a boom-box speaker output to the RF generator's modulation input. After inserting a CD, I powered the rig up and tuned to the appopriate RF frequency. All of a sudden, the biz dev guy's favorite radio station switched from hard rock to a Hungarian folk music format.
Another bit of fun involved taking the flash unit out of a disposable camera, mounting it behind the "message waiting" light in the engr. manager's phone, and running a wire so we could trip it from down the hall. We would set it off once or twice a day, at random times, illuminating his whole cube in brilliant white light. That went on for about two weeks with the manager getting progressively more concerned about his mental health, until one day we set it off when he happened to be looking right at it. Gig up.
It's VegEmite, not vegamite, but I'd agree it is a taste usually only acquired by Australians, I get South African or English Marmite rather. Vegemite would certainly bcause alarm to someone who wasn't used to it....
I love the mustard idea...However, the Australians eat one of the nastiest substances known to man, that is called "vegamite". For lack of a better description, it is a yeast paste. But that descrition falls far short of the actual taste--which will leave the average person alternating between wiping their tongue off with paper towels, and gargeling with the strongest solvent that they dare put in their mouth. So I tip my hat to your original idea, but there is rarely an idea so good, that it can't be improved on a little mit.