WowAce

Heads Up Display with Player and Target Info

Fires events whenever a raid member "fails".

A library to return spell duration and debuff type of a spellID.

KoS-Management Tool

mHud

Rep2 displays a message, which shows how much reputation you gained, and how much is needed until the next standing.

Loot management tool

FuBar_FuXPFu

Simple right click casting.

FuBar_MonkeyQuestFu

ImprovedRWF

Enable/Disable addons for your character in game

Clean looking square minimap with many options.

Generates and posts random Chuck Norris facts to a specified chat medium.

Displays the zone level ranage of the zone you are in and also gives you a suggest zone and instances to be in.

Displays friend notes in unit tooltips, at logon, and in /who results.

Tooltip scanning library.

Litmus

Adds party/raid role icons in useful places

Estimated time until current target will die.