I would really like alerts (like reddit does...an orange envelope or something similar)...when someone replies to my comment I don't want to have continually ch

I would really like alerts (like reddit does...an orange envelope or something similar)...when someone replies to my comment I don't want to have continually check to see if there are replies. I know there are a lot of people that don't want this for some reason or another. For this reason there should be an option to turn them on/off.