Remember Ring
The Remember Ring has a special nagging feature, using its "Hot Spot" technology that warms up to 120 degrees Fahrenheit for 10 seconds, every hour, on the hour, beginning 24 hours before that "special day," apparently honoring the anniversary of your voluntary servitude. That's supposed to be warm enough to be uncomfortable but not hot enough to burn you. The Remember Ring converts the heat from your hand into electricity using a micro-thermo pile, keeping that battery charged and its heat-bomb clock ticking away, ready to burn you again next year.
Tell the proprietors when your anniversary date is when you order the ring, and they'll program it for you.
I want to know what happens should it go wrong???
Will it nag you every day for the rest of your life? Will you be left with a finger?