I use the Google calendar, with different types of events in different colors sub-calendars

• One the things, that only I need to know (eg. Refill the automatic cat feeder, dentist appointment)
• one shared with the wife, so she can see, if I have plans to see friends or similar, and she has a similar I can see
• one shared for the daughters appointment
• one shared that contains my work schedule
• Public holidays (Maintained by Google, so always up to date)
• Birthdays and anniversaries All of them displayed on a widget