WowAce

Replacement for ActionButton_Show/HideOverlayGlow APIs

Creates and manages secure Action Buttons

Show item levels in the character frame

Collects Herbs, Mines, Gas Clouds, Archaeology, Treasure and Fishing locations and adds them to the worldmap and minimap

Modular casting bar.

Another HUD addon

Modular damage meter.

"Debug" code free since '93!

Allows you to view all items from all your characters on the same account, when-ever and where-ever you want.

Shows the possible loot from the bosses

The original HandyNotes source for where things are in Battle for Azeroth

Restores access to removed interface options in Legion

Postal: Enhanced Mailbox support

Core module for Loot and Looting-related UI improvements

A skinning engine for button-based add-ons.

Estimated range display. Type /rangedisplay for config

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

Library of compressed itemid sets.

Tracks rare drops, including companions and mounts

In-game theorycraft. Calculates actual damage/healing based on gear, talents and buffs.