I've been thinking about alternative calendars recently. This is quite interesting. I wonder if we will ever get to a point that we can have a "base 10" calendar (10 day weeks, 10 months in a year, etc.) I suppose in-grained traditions that are so hard to change (birthdays, memorials, etc.) make this nigh impossible.
Too much risk that 10 day weeks would end up still only having a 2 day weekend off of work leaving an 8 consecutive day work week.
The obvious conclusion is that they would have only 1 day off.