WowAce

Shows skills in a tooltip and allow them to be used. Also keeps track of Cooldowns.

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

BarAnnounce3

Displays classes and specialisation dependent stat priorities provided by icy-veins.com

Detects specific CDs and spellcasts

Shows mana usage as a percentage in a spells tooltip.

Review any raid or party members recent incoming combat along with health level.

Provides shareable notes and other information for your guild, party and raid community.

DarkCandy

Shows Status Bars that you can drag around and group up for your cooldowns

MendWatch

Allows you to preview weapon glow in Dressing Room.

Talented_Data

Separate indicator for your HoTs with timer.

GotWood

Enhancer

Doodle

Henge

Highly-configurable shield / absorb tracker.

Tracks interrupts