WowAce

OneChoice tries to help you reduce quest reward choices down to, ideally, one choice.

Adds resurrection and soulstone status to Grid, using LibResComm-1.0.

AltClick an item in your bag to add it a mail, auction, or trade frame, and alt-click to buy a stack if reagents.

LDB data source for Combat Tracking

Enables user defined sounds for Party, Guild, Raid and Custom Channel chat messages.

Allows the user to customize the the tooltip with lua-scripts

DeclineDuel

Adds a button to the quest completion interface which allows you to auto equips selected quest Item after completion

Outdated! Please use 'XLoot', available on Curse and WoWI

Adds Friend and Guild options to the context menu of player units.

FuBar_TransporterFu

SurgeonGeneral

Adds aura indicators to unit frames

Numen

Keeps track of time played and rested XP across your characters.

Building a Better Mailbox

Acolyte2

MendWatch

DHUD2

A simple addon that warns you if your pet isn't attacking while you're in combat.