I may as well amuse myself here:

My ideal calendar has 12 30 day months, days 0 to 29.

If it's 10th June and you have an appointment for 0 August, that's 50 days from now.

At the end of the year, a 5 or 6 day 'month' called Holiday. 30th December becomes Christmas Day (observed) and 0 January is still New Years. New Years Eve is either 5 or 6 Holiday.

6 Holiday would be a lot of fun. ^_^