WowAce

Reports in raid chat whenever a raid member "fails." /EnsidiaFails to configure.

Display aura information inside action buttons

Automated smart raid marking to speed up trash clearing in instance runs

Co-ordinated targetless Party and Raid wipe recovery. Evolved

Antagonist

Database of Diminishing return categories and general data

Show where the chests are for Withered Army Training

Queing of /who and SendWho() queries and a much better interface (see docs), with gurantee to be executed & callback.

manipulate the minimap in numerous ways; move, scale, skin.

A simple slash-command-based addon for querying item information from the Blizzard servers via ItemIDs and SpellIDs.

Database of Vendor locations for HandyNotes

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

Raid Frames using the oUF framework.

MorgDKP

Angry Assignments

Regain that wasted space!

Keeps track of your current location.

Set and manage character notes that are displayed in unit tooltips and /who results.

provides enchanters with a decent tool for managing their profession

XRS