WowAce

One-click smart mounting.

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

Taggle

Add-on that shows which battle pets can be farmed this week

Keeps track of healing spells cast by everyone in a group.

Welfare Epics

Bidder for DKP points. Usable as standalone bidder, or with DKP - Manager to manage points.

Open those clams (and other containers)

TrapBar

Uses guild notes to add alts' main names to chat windows and other places

SRA

ShadowGreenLight helps you decide if recasting SWP/Corruption is worthwhile

Color manipulation library.

Piece of mind by being one with your class.

LDB display for Oak Interrupts Broker

Watch tooltip updates to announce when you find specific objects

RaidHelper

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

Saves contents of your guild bank and sends/receives updates over the addon channel

FuBar_AlchemyFu