WowAce

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

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

Does stuff for sachmo

Tracks Raid/Instance/World Boss lockouts for all your characters, daily/weekly quests, currencies, trade cooldowns, and more!

A library to help with localization of in-game subzone names.

Shared handling of alternate identity data between addons.

Arena unit frames

Replacement for the default UI's StaticPopup dialogs.

Show item levels in the character frame

Provides one or many frames for dumping text into.

Simple Map Mod

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

A library to help with localization of bosses.

"Debug" code free since '93!

Restores access to removed interface options in Legion

Enables multi-line/unlimited-length pasting of text or commands into WoW

Library of compressed itemid sets.

Displays the locations of Lunar Festival elders.

Adirelle's bag addon.

A skinning engine for button-based add-ons.