Adding Feature to "Counter Up/Down" Widget

It would be really nice to add another "Counter Type"; something like "Specific Time". For instance, I'd like to have a Layout that starts running 30 minutes before the start of an event where it shows a countdown timer. Rather than specifying the date and time, just specify a duration, so it starts the specified countdown when the widget is initiated. This would allow the widget to be used as many times as needed without having to change the date and time for each event.