On the Sun/Solaris machines where I first worked, the `sl` command had an added bonus: it played a really loud "choo-choo" sound from the workstation's internal

On the Sun/Solaris machines where I first worked, the `sl` command had an added bonus: it played a really loud "choo-choo" sound from the workstation's internal speaker, regardless of volume or mute settings, so you always knew when someone fat-fingered their file listings, and much laughing was had by all. I very quickly learned to alias sl=ls in my shell rc, and it's still in there to this day, just in case...