WowAce

Shows a nice Soulstone Monitor.

JostleLib

Library to help with querying unit talents.

For Developers (of Addons which uses LibWho-2.0): show queues and queries in realtime

Provides the the health and target of by an unit targeted mob (meant to be used for tanks).

Puts a timer in /yell when you get Unbound Plague during the Heroic Professor Putricide encounter

Welfare Epics

TagCompiler-1.0

A loot distribution addon meant to improve master looting during raids.

XArt

Fancy up the PlayerPowerBarAlt frame

A 'channeling spell'-tracking addon for Affliction Warlocks. Drain Soul, Drain Life/Harvest Life and Malefic Grasp.

ERP

RaidGroupNumber

Menagerie

Right-click on minimap blips to open a targeting menu (out of combat).

LFD status via a DataBroker display rather than the minimap.

Shows a frame to track your debuff on Malygos in phase three.

Replacement of build-in loot frame

WoWonid