Question: How can I use innocent gadgets to needle people in my open office without getting caught?

Answer:
My original idea was to get a live parrot, and just train it to insult people by name in a large open office. This will be traced back to you pretty quickly, though, so add stealth to your strategy. There are many devices, and probably apps as well, which can record conversations for later playback, possibly remotely, when your target walks past your empty desk.

I would try to link the app to the target’s phone somehow, so that the target’s location is automatically fed into the app without any interference from you.

Here’s another one. A true story. One of our engineers placed a number of car-alarm devices in the ceiling of another associate’s private office, and set them off remotely throughout the day. The guy was trying to find the source of the noise which would stop beeping right around the time he got the ceiling tiles off. April Fool’s!