@Setanta,
Ok, I laughed but then I stopped. I once hired extra staff to help me complete "Project From Hell I" which, unfortunately, was followed by "II", but that's not the story. One of my key new hires was an Orthodox Jew who had to be off the roads in time for Friday Sabbath which begins at sunset on Friday.
The project began in April. We were working late hours by August and then pushing to close it out by the end of December. OOOPS! Sunset in Chicago in December is at 4:16pm. My client was based in CA which meant that it was noontime Friday when my key employee was shutting down for the week here. There were numerous occasions when I said, "We'll have to wait until Monday for that. The Sabbath has begun here."
I actually heard one person grumble... "how do I become an orthodox Jew?"