Guru Meditation
The Amiga's crash screen — a flashing red box with two hex numbers, named after an in-house yoga joke.
When AmigaOS hit an unrecoverable error it drew a thin, flashing red border around the screen reading "Software Failure", followed by two hexadecimal numbers: an error code and the address where it blew up. The system was dead; the only way out was to click and reboot. The PC world later landed on the Blue Screen of Death for the same job.
The name came from inside the Amiga team. The developers had a balance board, the Joyboard, and a running gag was to sit dead still on it — "guru meditation" — without setting anything off; whoever twitched got a Guru Meditation. From Kickstart 2.0 the wording changed to the drier "Software Failure", but the scene never called it anything but the guru. A wrong Kickstart version or a stray pointer was enough to summon it, even straight from Workbench.