WowAce

Show what quests have changed

Remember where rares were

Show the appearance of an item when you mouse over it

Show item levels in the character frame

Show a texture on demand

Where are the hidden treasures in Legion?

Should I send that recipe to my alt?

Drop the cheapest thing you're carrying

Where are the hidden treasures in Battle for Azeroth? Show in HandyNotes

Where the Lost and Found objects are

Where the Treasure Hunter objects are in Draenor

Quest information

From bags we came, to bank we return

Library to check whether an item is equipable / appropriate for a given class

Show vignette icons sooner

Where the lore is at

Make noise when the servr is going to restart

A library to help with localization of the output of UnitCreatureType.

Show all the leyline taps in Suramar

Teleporters in Suramar? Sure, why not?