I have several appointments/ commitments that are the same each time I use
them, but do not reoccur at set intervals.

ie, I always block out the same hours, place, and name for my volunteer
work, twice a month, but on random days, depending on how it fits into other
commitments.
Hair cuts, always with the sam stylist, salon, etc, but at different times.
I'd like to be able to select from a library of appointments/events and drop
them at the places needed in the calendar.