Our department computer lab has an ancient audio speaker wired to the central teacher console that nobody has touched since 2018.
Yesterday during our 2-hour dull Solid State Physics lecture, someone found the open Bluetooth receiver named 'LAB_AUDIO_SYSTEM_01' and connected to it from the last bench.
Instead of playing a joke, they queued up the lofi instrumental version of 'Kun Faya Kun' at 10% volume. The entire lab went dead quiet, and even the professor paused mid-equation, smiled, and said 'Chalo, mahaul accha hai' and kept writing.