WowAce

PT3Browser

Highly-configurable shield / absorb tracker.

Simple library that handles multiple levels of logging.

Open all your mail

KoS-Management Tool

Keeps track of quests.

Mutt (Macro Update Target Tool) provides slash-commands that can patch the predefined targets in your macros.

Litmus

Adds unreal tournament style sounds to PvP encounters.

Shows skills in a tooltip and allows them to be used.

Display aura information inside action buttons

Visualises healing.

A library to help with localization of Zones.

Cartographer_QuestObjectives

Switch macro depending on zones or BigWigs boss modules.

UnitActionBars

Library handling communcation for Magic* addons

Add-on that allows you to setup and quickly switch between different profiles of your action bars

Show what quests have changed

MorgDKP