WowAce

Keeps an eye on someone's distance from you, and alerts you if they get too far.

Warnings about tanking specific abilities

Counts stacked lifeblooms and uses progressive colors to indicate the active number of HOTs.

Centralised management hub for small tweak, interface and utility addons.

ItemRackFu

A collection management library similar to .NET's System.Linq

An attempt at giving a complete overview of Arena battles

The ultimate in lazy Ulduar raiding

Denial2

XP and Reputation bars

Damnation

LatencyAlert

Shows attachment count in Inbox icon.

Tracks and announces interrupts (eg. Hit/Miss/Immune) and is also able to track and report "wasted" interrupts (those which d...

World of Warcraft Textmate Bundle

ChatAssist2Options

A total number of quests Data Broker plugin.

Creates a broker plugin for all your broker launchers

Makes the Battle Objectives Frame movable

Show a bar indicating the unit's Burning Embers count.