Noise in the Ceiling
I'm currently attending a university, about to graduate this May. I live off campus in an apartment with 4 other roommates. Several weeks ago, I had an idea to play a prank on my neighboring roommate. I had heard about the ThinkGeek Annoy-a-Tron and thought it was an excellent idea for something like this. I wanted to one-up it, though. Using an Arduino and some other components my other roommates had lying around, I built a similar device that can be controlled over HTTP.
The noise device:
Pretty menacing, right? I wrapped it in a grocery bag, for dust shielding, but this seemed dangerous for static.
Here's the Mk II, which I switched to shortly thereafter:
I installed it 3 weeks ago, in the drop ceiling between our rooms. I thought he'd notice within several days.
The device listened over port 1337, and parsed the HTTP request to generate a particular tone. For example,
device:1337/1000 would sound at 1000Hz,
device:1337/2000 is 2000Hz, and so on.
I wrote a script to send it HTTP requests at a random interval, between 2 and 8 minutes (just like the Annoy-a-Tron). I ran this script all day, and all night, for at least a week.
At some time, I stopped running the script for whatever reason, but would casually check in and make the device beep manually every now and then.
My roommate never said anything. I assumed he couldn't hear it, despite the noise being definitely audible from my room.
Tonight, he noticed a power supply running into the drop ceiling of my room, on the wall adjacent to his room. He didn't know that this was for an Arduino in his ceiling, but suspected something. I turned up the intensity, and the rest of my roommates joined me in a hunt for the source of the noise. They, of course, had all known since I first installed it.
Finally my roommate realized the prank. He confessed that he heard the noise, every single time it sounded, and that he was convinced it was coming from his computer or television. He was afraid of saying something because he was afraid of sounding crazy.
Needless to say, this went on for a little longer than I intended. Worth it.