In Vernor Vinge's far future novel _A Deepness in the Sky_, there is a mention of a "programmer-archaeologist" who digs deep into layers and layers of legacy software of spaceships; it's tens of thousands of years of stuff built on top of each other.
It's mentioned that the deepest layers count time in seconds from the moment that humanity first landed on the moon of its home planet.
In fact, there’s an comment to the effect that the actual start time is about a million and a half seconds after the moon landing — which means the original time system is Unix-based...
I just love the title "Programmer-at-Arms." Some of the seat-of-the-pants work we do in industrial automation, making changes to a machine's operating logic while it's actually running in production, feels just like that.
It's mentioned that the deepest layers count time in seconds from the moment that humanity first landed on the moon of its home planet.