written in python/pyqt

an app that's
a) a calendar
b) a schedular - reminding you when important dates and times come up or are coming up
c) an alarm clock
d) a timer

features:
a: allows notes to be written on any date
b: gives you the option of how many days to start reminding you beforehand and how many hours/minutes before the actual time on that date.
c:
  supports multiple alarm clocks
  choose what sound the alarm clock uses
  possibility to override current global volume setting
can schedule alarms or reminders for:
  every X days, particular days of a week, or particular days of a month
  every X weeks, or particular weeks of a month
  every X months, or particular months every year

watch out for using timers to schedule the alarms. if there's a daylight savings change the timer may be late or early.