WowAce

On login, displays changes to your guild since the last time you logged in.

FuBar_FuXPFu

Does a /who search of multiple dungeons.

Information display for Hunters.

GatherHud for GatherMate2 with Routes support

Lists Pots and Herbs you got on all chars and allows you to specify color coding

Add-on that shows in a unit tooltip window a number of killed mobs of the same kind

Enhances the StackSplitFrame with numbered Buttons, a '1-Click Mode' and a 'Auto Split Mode'.

Shows who controls Wintergrasp and the time until the next battle.

Warns you with sounds when you gain different shaman spells.

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

RaidInfo

NBuffBars

Warnings about tanking specific abilities

Handles the assignment, coordination, and announcement of many parts of the Lich King encounter in Icecrown Citadel.

Sets the DND flag, when are in combat.

Displays info about who rolled Need/Greed/Pass on items that are currently rolled for

A Data Broker add-on for quickly switching your specialization with gear set and loot specialization.

Automatically sells low quality gray items and selected white items to the vendor.

Prospecting and Disenchanting Aide