Even the classical UNIX workstations.
Had a customer call me why the disk of one UNIX workstation filled up to 99, maybe 100%.
Lucky me, I could connect via modem and kermit to that system.
Turned out that during the managers two weeks vacation his secretary started the daily backup.
Backup device: /dev/rmt/0m
Since she was used to a PC keyboard, not to that somewhat special UNIX keyboard, she specified the backup device file as CTRL-7devCTRL-7rmtCTRL-70m
The backup ran until the disk was full..
But it was quick!