Other forums have this feature I particularly like where you can subscribe to a topic but choose to be notified less often than immediately. For very popular threads (like the Emisar D4 thread) there are way too many notifications if you log in and out frequently and would prefer to be notified on those more popular threads less often.
Typically i’ve seen it where you can choose, for each thread subscription, if you want to be notified immediately, once a day or once a week.