OpenKobold is an OpenSource device to make your friends (or foes) go mad.
The simplicity of psychological terror lies in the design -
OpenKobold emits a high-pitch noise at a random time.
Having a small-factor design (25x20mm) and a long silence period it is almost
impossible to locate the device.
And since MCU runs in-low power mode, it can last for years.
All hail mighty OpenKobold
Please don't kill each other...