What would be really cool is to make reminders that reminds you when you are in a special area.
For example:
When I am close to a special shop it reminds me to get that special battery that only them have.
When I get home it reminds me to do something in my home, take out the trash for example.
When I visit a friend I get a reminder about something I should inform him of.
Location-based notifiers instead of time-based (or a combination so it would not remind me to go to the store nearby in the middle of the night and its closed).