NoteblockTweak by CharlieJiang
A mod allows controling noteblocks by note like 'A#5'. Only compatible with Piano+ respack yet.
NotifyMe by 01101001#8125
If somebody says your name you will be notified with a sound! Currently works on Hypixel and a few other big servers. If you want it to work elsewhere not much I can do.
Nuclear Control by Shedar
Nuclear Control, an Industrial Craft 2 addon that allows you to build efficient monitoring and notification system for your nuclear reactor. Also you can use Howler Alarm and Industrial Alarm in any case when you want industrial-style notification/alarming system.