WowAce

A powerful, comprehensive utilty for displaying graphics and information based on buffs, debuffs, and other triggers.

In-game theorycraft. Calculates actual damage/healing based on gear, talents and buffs.

Numerical and graphical display of Combo Points and similar buffs/debuffs. Also tracks Holy Power and Soul Shards.

Display auras on action buttons.

Rebuff yourself with the mousewheel.

EBB adds groups of bars to your screen showing you which (de)buffs currently affect your toon or some other units.

Display aura information inside action buttons

Co-ordinated targetless Party and Raid wipe recovery. Evolved

Track all threat redirection ability transfers and cooldowns (Misdirection and Tricks of the Trade).

Checks your gear before bosses and yells at you if you're an idiot

Cryolysis 2

GotWood

SacredBuff

Healer gear benchmark

Compact & customizable filtering, monitoring and grouping of buffs and debuffs

Additional information about player spells.

Kaliban's Class Loot List Star Display

Tracks skill and tradeskill costs and progressions, as well as trainer locations.

Textures for Stop Motion

Announces Mage Spells in chat.