The 13 month per calendar year (Mayan calendar) just makes so much sense as a web developer but somehow as a human it also seems hella mundane to have the same 28 day cycle repeated. Maybe that last day of the year party would make up for it though.
I quite like the hobbit calendar. 12 months of 30 days each, plus 5 (or 6) extra days that don't belong to a month and are celebration days. Mid-year day and the leap day don't have a day of the week, so each date always is the same day of the week.
The only disadvantage I can see is that you’d have your birthday in the same day of the week every year. If you are born on a Monday, you’ll celebrate on a Monday every year in your life.
I'm so familiar with the Gregorian calendar that I would prefer the International Fixed Calendar (13 months of 28 days + Leap Day and Year Day) with its yearly synchronization over the Mayan calendar.
