Unix Recovery Legend (1986)
I once fat-fingered crontab -r instead of crontab -e on a production accounting system running Solaris which immediately wiped out something on the order of about 200 cron entries.  Had to restore the contents from off-site backup tapes.The jokes circling the office for the next few weeks were all variations on "Remember alyandon - r doesn't mean 'revise'".  :(